4f20faaa43
# Objective - Implements a more efficient, GPU-driven (https://github.com/bevyengine/bevy/issues/1342) rendering pipeline based on meshlets. - Meshes are split into small clusters of triangles called meshlets, each of which acts as a mini index buffer into the larger mesh data. Meshlets can be compressed, streamed, culled, and batched much more efficiently than monolithic meshes.   # Misc * Future work: https://github.com/bevyengine/bevy/issues/11518 * Nanite reference: https://advances.realtimerendering.com/s2021/Karis_Nanite_SIGGRAPH_Advances_2021_final.pdf Two pass occlusion culling explained very well: https://medium.com/@mil_kru/two-pass-occlusion-culling-4100edcad501 --------- Co-authored-by: Ricky Taylor <rickytaylor26@gmail.com> Co-authored-by: vero <email@atlasdostal.com> Co-authored-by: François <mockersf@gmail.com> Co-authored-by: atlas dostal <rodol@rivalrebels.com>
880 lines
38 KiB
Rust
880 lines
38 KiB
Rust
use bevy_asset::Asset;
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use bevy_color::Alpha;
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use bevy_math::{Affine2, Mat3, Vec4};
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use bevy_reflect::{std_traits::ReflectDefault, Reflect};
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use bevy_render::{
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mesh::MeshVertexBufferLayoutRef, render_asset::RenderAssets, render_resource::*,
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};
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use crate::deferred::DEFAULT_PBR_DEFERRED_LIGHTING_PASS_ID;
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use crate::*;
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/// A material with "standard" properties used in PBR lighting
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/// Standard property values with pictures here
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/// <https://google.github.io/filament/Material%20Properties.pdf>.
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///
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/// May be created directly from a [`Color`] or an [`Image`].
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#[derive(Asset, AsBindGroup, Reflect, Debug, Clone)]
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#[bind_group_data(StandardMaterialKey)]
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#[uniform(0, StandardMaterialUniform)]
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#[reflect(Default, Debug)]
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pub struct StandardMaterial {
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/// The color of the surface of the material before lighting.
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///
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/// Doubles as diffuse albedo for non-metallic, specular for metallic and a mix for everything
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/// in between. If used together with a `base_color_texture`, this is factored into the final
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/// base color as `base_color * base_color_texture_value`
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///
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/// Defaults to [`Color::WHITE`].
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pub base_color: Color,
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/// The texture component of the material's color before lighting.
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/// The actual pre-lighting color is `base_color * this_texture`.
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///
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/// See [`base_color`] for details.
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///
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/// You should set `base_color` to [`Color::WHITE`] (the default)
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/// if you want the texture to show as-is.
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///
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/// Setting `base_color` to something else than white will tint
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/// the texture. For example, setting `base_color` to pure red will
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/// tint the texture red.
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///
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/// [`base_color`]: StandardMaterial::base_color
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#[texture(1)]
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#[sampler(2)]
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#[dependency]
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pub base_color_texture: Option<Handle<Image>>,
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// Use a color for user friendliness even though we technically don't use the alpha channel
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// Might be used in the future for exposure correction in HDR
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/// Color the material "emits" to the camera.
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///
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/// This is typically used for monitor screens or LED lights.
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/// Anything that can be visible even in darkness.
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///
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/// The emissive color is added to what would otherwise be the material's visible color.
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/// This means that for a light emissive value, in darkness,
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/// you will mostly see the emissive component.
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///
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/// The default emissive color is [`Color::BLACK`], which doesn't add anything to the material color.
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///
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/// To increase emissive strength, channel values for `emissive`
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/// colors can exceed `1.0`. For instance, a `base_color` of
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/// `Color::linear_rgb(1.0, 0.0, 0.0)` represents the brightest
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/// red for objects that reflect light, but an emissive color
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/// like `Color::linear_rgb(1000.0, 0.0, 0.0)` can be used to create
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/// intensely bright red emissive effects.
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///
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/// Increasing the emissive strength of the color will impact visual effects
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/// like bloom, but it's important to note that **an emissive material won't
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/// light up surrounding areas like a light source**,
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/// it just adds a value to the color seen on screen.
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pub emissive: Color,
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/// The emissive map, multiplies pixels with [`emissive`]
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/// to get the final "emitting" color of a surface.
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///
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/// This color is multiplied by [`emissive`] to get the final emitted color.
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/// Meaning that you should set [`emissive`] to [`Color::WHITE`]
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/// if you want to use the full range of color of the emissive texture.
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///
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/// [`emissive`]: StandardMaterial::emissive
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#[texture(3)]
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#[sampler(4)]
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#[dependency]
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pub emissive_texture: Option<Handle<Image>>,
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/// Linear perceptual roughness, clamped to `[0.089, 1.0]` in the shader.
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///
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/// Defaults to `0.5`.
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///
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/// Low values result in a "glossy" material with specular highlights,
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/// while values close to `1` result in rough materials.
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///
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/// If used together with a roughness/metallic texture, this is factored into the final base
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/// color as `roughness * roughness_texture_value`.
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///
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/// 0.089 is the minimum floating point value that won't be rounded down to 0 in the
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/// calculations used.
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//
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// Technically for 32-bit floats, 0.045 could be used.
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// See <https://google.github.io/filament/Filament.html#materialsystem/parameterization/>
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pub perceptual_roughness: f32,
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/// How "metallic" the material appears, within `[0.0, 1.0]`.
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///
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/// This should be set to 0.0 for dielectric materials or 1.0 for metallic materials.
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/// For a hybrid surface such as corroded metal, you may need to use in-between values.
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///
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/// Defaults to `0.00`, for dielectric.
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///
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/// If used together with a roughness/metallic texture, this is factored into the final base
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/// color as `metallic * metallic_texture_value`.
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pub metallic: f32,
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/// Metallic and roughness maps, stored as a single texture.
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///
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/// The blue channel contains metallic values,
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/// and the green channel contains the roughness values.
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/// Other channels are unused.
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///
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/// Those values are multiplied by the scalar ones of the material,
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/// see [`metallic`] and [`perceptual_roughness`] for details.
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///
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/// Note that with the default values of [`metallic`] and [`perceptual_roughness`],
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/// setting this texture has no effect. If you want to exclusively use the
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/// `metallic_roughness_texture` values for your material, make sure to set [`metallic`]
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/// and [`perceptual_roughness`] to `1.0`.
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///
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/// [`metallic`]: StandardMaterial::metallic
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/// [`perceptual_roughness`]: StandardMaterial::perceptual_roughness
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#[texture(5)]
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#[sampler(6)]
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#[dependency]
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pub metallic_roughness_texture: Option<Handle<Image>>,
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/// Specular intensity for non-metals on a linear scale of `[0.0, 1.0]`.
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///
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/// Use the value as a way to control the intensity of the
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/// specular highlight of the material, i.e. how reflective is the material,
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/// rather than the physical property "reflectance."
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///
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/// Set to `0.0`, no specular highlight is visible, the highlight is strongest
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/// when `reflectance` is set to `1.0`.
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///
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/// Defaults to `0.5` which is mapped to 4% reflectance in the shader.
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#[doc(alias = "specular_intensity")]
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pub reflectance: f32,
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/// The amount of light transmitted _diffusely_ through the material (i.e. “translucency”)
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///
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/// Implemented as a second, flipped [Lambertian diffuse](https://en.wikipedia.org/wiki/Lambertian_reflectance) lobe,
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/// which provides an inexpensive but plausible approximation of translucency for thin dieletric objects (e.g. paper,
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/// leaves, some fabrics) or thicker volumetric materials with short scattering distances (e.g. porcelain, wax).
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///
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/// For specular transmission usecases with refraction (e.g. glass) use the [`StandardMaterial::specular_transmission`] and
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/// [`StandardMaterial::ior`] properties instead.
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///
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/// - When set to `0.0` (the default) no diffuse light is transmitted;
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/// - When set to `1.0` all diffuse light is transmitted through the material;
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/// - Values higher than `0.5` will cause more diffuse light to be transmitted than reflected, resulting in a “darker”
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/// appearance on the side facing the light than the opposite side. (e.g. plant leaves)
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///
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/// ## Notes
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///
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/// - The material's [`StandardMaterial::base_color`] also modulates the transmitted light;
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/// - To receive transmitted shadows on the diffuse transmission lobe (i.e. the “backside”) of the material,
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/// use the [`TransmittedShadowReceiver`] component.
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#[doc(alias = "translucency")]
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pub diffuse_transmission: f32,
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/// A map that modulates diffuse transmission via its alpha channel. Multiplied by [`StandardMaterial::diffuse_transmission`]
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/// to obtain the final result.
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///
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/// **Important:** The [`StandardMaterial::diffuse_transmission`] property must be set to a value higher than 0.0,
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/// or this texture won't have any effect.
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#[texture(17)]
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#[sampler(18)]
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#[cfg(feature = "pbr_transmission_textures")]
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pub diffuse_transmission_texture: Option<Handle<Image>>,
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/// The amount of light transmitted _specularly_ through the material (i.e. via refraction)
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///
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/// - When set to `0.0` (the default) no light is transmitted.
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/// - When set to `1.0` all light is transmitted through the material.
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///
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/// The material's [`StandardMaterial::base_color`] also modulates the transmitted light.
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///
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/// **Note:** Typically used in conjunction with [`StandardMaterial::thickness`], [`StandardMaterial::ior`] and [`StandardMaterial::perceptual_roughness`].
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///
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/// ## Performance
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///
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/// Specular transmission is implemented as a relatively expensive screen-space effect that allows ocluded objects to be seen through the material,
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/// with distortion and blur effects.
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///
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/// - [`Camera3d::screen_space_specular_transmission_steps`](bevy_core_pipeline::core_3d::Camera3d::screen_space_specular_transmission_steps) can be used to enable transmissive objects
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/// to be seen through other transmissive objects, at the cost of additional draw calls and texture copies; (Use with caution!)
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/// - If a simplified approximation of specular transmission using only environment map lighting is sufficient, consider setting
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/// [`Camera3d::screen_space_specular_transmission_steps`](bevy_core_pipeline::core_3d::Camera3d::screen_space_specular_transmission_steps) to `0`.
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/// - If purely diffuse light transmission is needed, (i.e. “translucency”) consider using [`StandardMaterial::diffuse_transmission`] instead,
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/// for a much less expensive effect.
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/// - Specular transmission is rendered before alpha blending, so any material with [`AlphaMode::Blend`], [`AlphaMode::Premultiplied`], [`AlphaMode::Add`] or [`AlphaMode::Multiply`]
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/// won't be visible through specular transmissive materials.
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#[doc(alias = "refraction")]
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pub specular_transmission: f32,
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/// A map that modulates specular transmission via its red channel. Multiplied by [`StandardMaterial::specular_transmission`]
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/// to obtain the final result.
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///
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/// **Important:** The [`StandardMaterial::specular_transmission`] property must be set to a value higher than 0.0,
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/// or this texture won't have any effect.
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#[texture(13)]
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#[sampler(14)]
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#[cfg(feature = "pbr_transmission_textures")]
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pub specular_transmission_texture: Option<Handle<Image>>,
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/// Thickness of the volume beneath the material surface.
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///
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/// When set to `0.0` (the default) the material appears as an infinitely-thin film,
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/// transmitting light without distorting it.
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///
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/// When set to any other value, the material distorts light like a thick lens.
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///
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/// **Note:** Typically used in conjunction with [`StandardMaterial::specular_transmission`] and [`StandardMaterial::ior`], or with
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/// [`StandardMaterial::diffuse_transmission`].
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#[doc(alias = "volume")]
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#[doc(alias = "thin_walled")]
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pub thickness: f32,
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/// A map that modulates thickness via its green channel. Multiplied by [`StandardMaterial::thickness`]
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/// to obtain the final result.
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///
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/// **Important:** The [`StandardMaterial::thickness`] property must be set to a value higher than 0.0,
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/// or this texture won't have any effect.
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#[texture(15)]
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#[sampler(16)]
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#[cfg(feature = "pbr_transmission_textures")]
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pub thickness_texture: Option<Handle<Image>>,
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/// The [index of refraction](https://en.wikipedia.org/wiki/Refractive_index) of the material.
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///
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/// Defaults to 1.5.
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///
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/// | Material | Index of Refraction |
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/// |:----------------|:---------------------|
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/// | Vacuum | 1 |
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/// | Air | 1.00 |
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/// | Ice | 1.31 |
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/// | Water | 1.33 |
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/// | Eyes | 1.38 |
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/// | Quartz | 1.46 |
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/// | Olive Oil | 1.47 |
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/// | Honey | 1.49 |
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/// | Acrylic | 1.49 |
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/// | Window Glass | 1.52 |
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/// | Polycarbonate | 1.58 |
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/// | Flint Glass | 1.69 |
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/// | Ruby | 1.71 |
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/// | Glycerine | 1.74 |
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/// | Sapphire | 1.77 |
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/// | Cubic Zirconia | 2.15 |
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/// | Diamond | 2.42 |
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/// | Moissanite | 2.65 |
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///
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/// **Note:** Typically used in conjunction with [`StandardMaterial::specular_transmission`] and [`StandardMaterial::thickness`].
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#[doc(alias = "index_of_refraction")]
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#[doc(alias = "refraction_index")]
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#[doc(alias = "refractive_index")]
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pub ior: f32,
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/// How far, on average, light travels through the volume beneath the material's
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/// surface before being absorbed.
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///
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/// Defaults to [`f32::INFINITY`], i.e. light is never absorbed.
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///
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/// **Note:** To have any effect, must be used in conjunction with:
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/// - [`StandardMaterial::attenuation_color`];
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/// - [`StandardMaterial::thickness`];
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/// - [`StandardMaterial::diffuse_transmission`] or [`StandardMaterial::specular_transmission`].
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#[doc(alias = "absorption_distance")]
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#[doc(alias = "extinction_distance")]
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pub attenuation_distance: f32,
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/// The resulting (non-absorbed) color after white light travels through the attenuation distance.
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///
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/// Defaults to [`Color::WHITE`], i.e. no change.
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///
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/// **Note:** To have any effect, must be used in conjunction with:
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/// - [`StandardMaterial::attenuation_distance`];
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/// - [`StandardMaterial::thickness`];
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/// - [`StandardMaterial::diffuse_transmission`] or [`StandardMaterial::specular_transmission`].
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#[doc(alias = "absorption_color")]
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#[doc(alias = "extinction_color")]
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pub attenuation_color: Color,
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/// Used to fake the lighting of bumps and dents on a material.
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///
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/// A typical usage would be faking cobblestones on a flat plane mesh in 3D.
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///
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/// # Notes
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///
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/// Normal mapping with `StandardMaterial` and the core bevy PBR shaders requires:
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/// - A normal map texture
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/// - Vertex UVs
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/// - Vertex tangents
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/// - Vertex normals
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///
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/// Tangents do not have to be stored in your model,
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/// they can be generated using the [`Mesh::generate_tangents`] or
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/// [`Mesh::with_generated_tangents`] methods.
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/// If your material has a normal map, but still renders as a flat surface,
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/// make sure your meshes have their tangents set.
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///
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/// [`Mesh::generate_tangents`]: bevy_render::mesh::Mesh::generate_tangents
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/// [`Mesh::with_generated_tangents`]: bevy_render::mesh::Mesh::with_generated_tangents
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#[texture(9)]
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#[sampler(10)]
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#[dependency]
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pub normal_map_texture: Option<Handle<Image>>,
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/// Normal map textures authored for DirectX have their y-component flipped. Set this to flip
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/// it to right-handed conventions.
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pub flip_normal_map_y: bool,
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/// Specifies the level of exposure to ambient light.
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///
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/// This is usually generated and stored automatically ("baked") by 3D-modelling software.
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///
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/// Typically, steep concave parts of a model (such as the armpit of a shirt) are darker,
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/// because they have little exposure to light.
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/// An occlusion map specifies those parts of the model that light doesn't reach well.
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///
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/// The material will be less lit in places where this texture is dark.
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/// This is similar to ambient occlusion, but built into the model.
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#[texture(7)]
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#[sampler(8)]
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#[dependency]
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pub occlusion_texture: Option<Handle<Image>>,
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/// Support two-sided lighting by automatically flipping the normals for "back" faces
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/// within the PBR lighting shader.
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///
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/// Defaults to `false`.
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/// This does not automatically configure backface culling,
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/// which can be done via `cull_mode`.
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pub double_sided: bool,
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/// Whether to cull the "front", "back" or neither side of a mesh.
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/// If set to `None`, the two sides of the mesh are visible.
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///
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/// Defaults to `Some(Face::Back)`.
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/// In bevy, the order of declaration of a triangle's vertices
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/// in [`Mesh`] defines the triangle's front face.
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///
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/// When a triangle is in a viewport,
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/// if its vertices appear counter-clockwise from the viewport's perspective,
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/// then the viewport is seeing the triangle's front face.
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/// Conversely, if the vertices appear clockwise, you are seeing the back face.
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///
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/// In short, in bevy, front faces winds counter-clockwise.
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///
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/// Your 3D editing software should manage all of that.
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///
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/// [`Mesh`]: bevy_render::mesh::Mesh
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// TODO: include this in reflection somehow (maybe via remote types like serde https://serde.rs/remote-derive.html)
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#[reflect(ignore)]
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pub cull_mode: Option<Face>,
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/// Whether to apply only the base color to this material.
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///
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/// Normals, occlusion textures, roughness, metallic, reflectance, emissive,
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/// shadows, alpha mode and ambient light are ignored if this is set to `true`.
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pub unlit: bool,
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/// Whether to enable fog for this material.
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pub fog_enabled: bool,
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/// How to apply the alpha channel of the `base_color_texture`.
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///
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/// See [`AlphaMode`] for details. Defaults to [`AlphaMode::Opaque`].
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pub alpha_mode: AlphaMode,
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/// Adjust rendered depth.
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///
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/// A material with a positive depth bias will render closer to the
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/// camera while negative values cause the material to render behind
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/// other objects. This is independent of the viewport.
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///
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/// `depth_bias` affects render ordering and depth write operations
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/// using the `wgpu::DepthBiasState::Constant` field.
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///
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/// [z-fighting]: https://en.wikipedia.org/wiki/Z-fighting
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pub depth_bias: f32,
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/// The depth map used for [parallax mapping].
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///
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/// It is a greyscale image where white represents bottom and black the top.
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/// If this field is set, bevy will apply [parallax mapping].
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/// Parallax mapping, unlike simple normal maps, will move the texture
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/// coordinate according to the current perspective,
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/// giving actual depth to the texture.
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///
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/// The visual result is similar to a displacement map,
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/// but does not require additional geometry.
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///
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/// Use the [`parallax_depth_scale`] field to control the depth of the parallax.
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///
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/// ## Limitations
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///
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/// - It will look weird on bent/non-planar surfaces.
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/// - The depth of the pixel does not reflect its visual position, resulting
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/// in artifacts for depth-dependent features such as fog or SSAO.
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/// - For the same reason, the geometry silhouette will always be
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/// the one of the actual geometry, not the parallaxed version, resulting
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/// in awkward looks on intersecting parallaxed surfaces.
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///
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/// ## Performance
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///
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/// Parallax mapping requires multiple texture lookups, proportional to
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/// [`max_parallax_layer_count`], which might be costly.
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///
|
||
/// Use the [`parallax_mapping_method`] and [`max_parallax_layer_count`] fields
|
||
/// to tweak the shader, trading graphical quality for performance.
|
||
///
|
||
/// To improve performance, set your `depth_map`'s [`Image::sampler`]
|
||
/// filter mode to `FilterMode::Nearest`, as [this paper] indicates, it improves
|
||
/// performance a bit.
|
||
///
|
||
/// To reduce artifacts, avoid steep changes in depth, blurring the depth
|
||
/// map helps with this.
|
||
///
|
||
/// Larger depth maps haves a disproportionate performance impact.
|
||
///
|
||
/// [this paper]: https://www.diva-portal.org/smash/get/diva2:831762/FULLTEXT01.pdf
|
||
/// [parallax mapping]: https://en.wikipedia.org/wiki/Parallax_mapping
|
||
/// [`parallax_depth_scale`]: StandardMaterial::parallax_depth_scale
|
||
/// [`parallax_mapping_method`]: StandardMaterial::parallax_mapping_method
|
||
/// [`max_parallax_layer_count`]: StandardMaterial::max_parallax_layer_count
|
||
#[texture(11)]
|
||
#[sampler(12)]
|
||
#[dependency]
|
||
pub depth_map: Option<Handle<Image>>,
|
||
|
||
/// How deep the offset introduced by the depth map should be.
|
||
///
|
||
/// Default is `0.1`, anything over that value may look distorted.
|
||
/// Lower values lessen the effect.
|
||
///
|
||
/// The depth is relative to texture size. This means that if your texture
|
||
/// occupies a surface of `1` world unit, and `parallax_depth_scale` is `0.1`, then
|
||
/// the in-world depth will be of `0.1` world units.
|
||
/// If the texture stretches for `10` world units, then the final depth
|
||
/// will be of `1` world unit.
|
||
pub parallax_depth_scale: f32,
|
||
|
||
/// Which parallax mapping method to use.
|
||
///
|
||
/// We recommend that all objects use the same [`ParallaxMappingMethod`], to avoid
|
||
/// duplicating and running two shaders.
|
||
pub parallax_mapping_method: ParallaxMappingMethod,
|
||
|
||
/// In how many layers to split the depth maps for parallax mapping.
|
||
///
|
||
/// If you are seeing jaggy edges, increase this value.
|
||
/// However, this incurs a performance cost.
|
||
///
|
||
/// Dependent on the situation, switching to [`ParallaxMappingMethod::Relief`]
|
||
/// and keeping this value low might have better performance than increasing the
|
||
/// layer count while using [`ParallaxMappingMethod::Occlusion`].
|
||
///
|
||
/// Default is `16.0`.
|
||
pub max_parallax_layer_count: f32,
|
||
|
||
/// The exposure (brightness) level of the lightmap, if present.
|
||
pub lightmap_exposure: f32,
|
||
|
||
/// Render method used for opaque materials. (Where `alpha_mode` is [`AlphaMode::Opaque`] or [`AlphaMode::Mask`])
|
||
pub opaque_render_method: OpaqueRendererMethod,
|
||
|
||
/// Used for selecting the deferred lighting pass for deferred materials.
|
||
/// Default is [`DEFAULT_PBR_DEFERRED_LIGHTING_PASS_ID`] for default
|
||
/// PBR deferred lighting pass. Ignored in the case of forward materials.
|
||
pub deferred_lighting_pass_id: u8,
|
||
|
||
/// The transform applied to the UVs corresponding to ATTRIBUTE_UV_0 on the mesh before sampling. Default is identity.
|
||
pub uv_transform: Affine2,
|
||
}
|
||
|
||
impl Default for StandardMaterial {
|
||
fn default() -> Self {
|
||
StandardMaterial {
|
||
// White because it gets multiplied with texture values if someone uses
|
||
// a texture.
|
||
base_color: Color::WHITE,
|
||
base_color_texture: None,
|
||
emissive: Color::BLACK,
|
||
emissive_texture: None,
|
||
// Matches Blender's default roughness.
|
||
perceptual_roughness: 0.5,
|
||
// Metallic should generally be set to 0.0 or 1.0.
|
||
metallic: 0.0,
|
||
metallic_roughness_texture: None,
|
||
// Minimum real-world reflectance is 2%, most materials between 2-5%
|
||
// Expressed in a linear scale and equivalent to 4% reflectance see
|
||
// <https://google.github.io/filament/Material%20Properties.pdf>
|
||
reflectance: 0.5,
|
||
diffuse_transmission: 0.0,
|
||
#[cfg(feature = "pbr_transmission_textures")]
|
||
diffuse_transmission_texture: None,
|
||
specular_transmission: 0.0,
|
||
#[cfg(feature = "pbr_transmission_textures")]
|
||
specular_transmission_texture: None,
|
||
thickness: 0.0,
|
||
#[cfg(feature = "pbr_transmission_textures")]
|
||
thickness_texture: None,
|
||
ior: 1.5,
|
||
attenuation_color: Color::WHITE,
|
||
attenuation_distance: f32::INFINITY,
|
||
occlusion_texture: None,
|
||
normal_map_texture: None,
|
||
flip_normal_map_y: false,
|
||
double_sided: false,
|
||
cull_mode: Some(Face::Back),
|
||
unlit: false,
|
||
fog_enabled: true,
|
||
alpha_mode: AlphaMode::Opaque,
|
||
depth_bias: 0.0,
|
||
depth_map: None,
|
||
parallax_depth_scale: 0.1,
|
||
max_parallax_layer_count: 16.0,
|
||
lightmap_exposure: 1.0,
|
||
parallax_mapping_method: ParallaxMappingMethod::Occlusion,
|
||
opaque_render_method: OpaqueRendererMethod::Auto,
|
||
deferred_lighting_pass_id: DEFAULT_PBR_DEFERRED_LIGHTING_PASS_ID,
|
||
uv_transform: Affine2::IDENTITY,
|
||
}
|
||
}
|
||
}
|
||
|
||
impl From<Color> for StandardMaterial {
|
||
fn from(color: Color) -> Self {
|
||
StandardMaterial {
|
||
base_color: color,
|
||
alpha_mode: if color.alpha() < 1.0 {
|
||
AlphaMode::Blend
|
||
} else {
|
||
AlphaMode::Opaque
|
||
},
|
||
..Default::default()
|
||
}
|
||
}
|
||
}
|
||
|
||
impl From<Handle<Image>> for StandardMaterial {
|
||
fn from(texture: Handle<Image>) -> Self {
|
||
StandardMaterial {
|
||
base_color_texture: Some(texture),
|
||
..Default::default()
|
||
}
|
||
}
|
||
}
|
||
|
||
// NOTE: These must match the bit flags in bevy_pbr/src/render/pbr_types.wgsl!
|
||
bitflags::bitflags! {
|
||
/// Bitflags info about the material a shader is currently rendering.
|
||
/// This is accessible in the shader in the [`StandardMaterialUniform`]
|
||
#[repr(transparent)]
|
||
pub struct StandardMaterialFlags: u32 {
|
||
const BASE_COLOR_TEXTURE = 1 << 0;
|
||
const EMISSIVE_TEXTURE = 1 << 1;
|
||
const METALLIC_ROUGHNESS_TEXTURE = 1 << 2;
|
||
const OCCLUSION_TEXTURE = 1 << 3;
|
||
const DOUBLE_SIDED = 1 << 4;
|
||
const UNLIT = 1 << 5;
|
||
const TWO_COMPONENT_NORMAL_MAP = 1 << 6;
|
||
const FLIP_NORMAL_MAP_Y = 1 << 7;
|
||
const FOG_ENABLED = 1 << 8;
|
||
const DEPTH_MAP = 1 << 9; // Used for parallax mapping
|
||
const SPECULAR_TRANSMISSION_TEXTURE = 1 << 10;
|
||
const THICKNESS_TEXTURE = 1 << 11;
|
||
const DIFFUSE_TRANSMISSION_TEXTURE = 1 << 12;
|
||
const ATTENUATION_ENABLED = 1 << 13;
|
||
const ALPHA_MODE_RESERVED_BITS = Self::ALPHA_MODE_MASK_BITS << Self::ALPHA_MODE_SHIFT_BITS; // ← Bitmask reserving bits for the `AlphaMode`
|
||
const ALPHA_MODE_OPAQUE = 0 << Self::ALPHA_MODE_SHIFT_BITS; // ← Values are just sequential values bitshifted into
|
||
const ALPHA_MODE_MASK = 1 << Self::ALPHA_MODE_SHIFT_BITS; // the bitmask, and can range from 0 to 7.
|
||
const ALPHA_MODE_BLEND = 2 << Self::ALPHA_MODE_SHIFT_BITS; //
|
||
const ALPHA_MODE_PREMULTIPLIED = 3 << Self::ALPHA_MODE_SHIFT_BITS; //
|
||
const ALPHA_MODE_ADD = 4 << Self::ALPHA_MODE_SHIFT_BITS; // Right now only values 0–5 are used, which still gives
|
||
const ALPHA_MODE_MULTIPLY = 5 << Self::ALPHA_MODE_SHIFT_BITS; // ← us "room" for two more modes without adding more bits
|
||
const NONE = 0;
|
||
const UNINITIALIZED = 0xFFFF;
|
||
}
|
||
}
|
||
|
||
impl StandardMaterialFlags {
|
||
const ALPHA_MODE_MASK_BITS: u32 = 0b111;
|
||
const ALPHA_MODE_SHIFT_BITS: u32 = 32 - Self::ALPHA_MODE_MASK_BITS.count_ones();
|
||
}
|
||
|
||
/// The GPU representation of the uniform data of a [`StandardMaterial`].
|
||
#[derive(Clone, Default, ShaderType)]
|
||
pub struct StandardMaterialUniform {
|
||
/// Doubles as diffuse albedo for non-metallic, specular for metallic and a mix for everything
|
||
/// in between.
|
||
pub base_color: Vec4,
|
||
// Use a color for user-friendliness even though we technically don't use the alpha channel
|
||
// Might be used in the future for exposure correction in HDR
|
||
pub emissive: Vec4,
|
||
/// Color white light takes after travelling through the attenuation distance underneath the material surface
|
||
pub attenuation_color: Vec4,
|
||
/// The transform applied to the UVs corresponding to ATTRIBUTE_UV_0 on the mesh before sampling. Default is identity.
|
||
pub uv_transform: Mat3,
|
||
/// Linear perceptual roughness, clamped to [0.089, 1.0] in the shader
|
||
/// Defaults to minimum of 0.089
|
||
pub roughness: f32,
|
||
/// From [0.0, 1.0], dielectric to pure metallic
|
||
pub metallic: f32,
|
||
/// Specular intensity for non-metals on a linear scale of [0.0, 1.0]
|
||
/// defaults to 0.5 which is mapped to 4% reflectance in the shader
|
||
pub reflectance: f32,
|
||
/// Amount of diffuse light transmitted through the material
|
||
pub diffuse_transmission: f32,
|
||
/// Amount of specular light transmitted through the material
|
||
pub specular_transmission: f32,
|
||
/// Thickness of the volume underneath the material surface
|
||
pub thickness: f32,
|
||
/// Index of Refraction
|
||
pub ior: f32,
|
||
/// How far light travels through the volume underneath the material surface before being absorbed
|
||
pub attenuation_distance: f32,
|
||
/// The [`StandardMaterialFlags`] accessible in the `wgsl` shader.
|
||
pub flags: u32,
|
||
/// When the alpha mode mask flag is set, any base color alpha above this cutoff means fully opaque,
|
||
/// and any below means fully transparent.
|
||
pub alpha_cutoff: f32,
|
||
/// The depth of the [`StandardMaterial::depth_map`] to apply.
|
||
pub parallax_depth_scale: f32,
|
||
/// In how many layers to split the depth maps for Steep parallax mapping.
|
||
///
|
||
/// If your `parallax_depth_scale` is >0.1 and you are seeing jaggy edges,
|
||
/// increase this value. However, this incurs a performance cost.
|
||
pub max_parallax_layer_count: f32,
|
||
/// The exposure (brightness) level of the lightmap, if present.
|
||
pub lightmap_exposure: f32,
|
||
/// Using [`ParallaxMappingMethod::Relief`], how many additional
|
||
/// steps to use at most to find the depth value.
|
||
pub max_relief_mapping_search_steps: u32,
|
||
/// ID for specifying which deferred lighting pass should be used for rendering this material, if any.
|
||
pub deferred_lighting_pass_id: u32,
|
||
}
|
||
|
||
impl AsBindGroupShaderType<StandardMaterialUniform> for StandardMaterial {
|
||
fn as_bind_group_shader_type(&self, images: &RenderAssets<Image>) -> StandardMaterialUniform {
|
||
let mut flags = StandardMaterialFlags::NONE;
|
||
if self.base_color_texture.is_some() {
|
||
flags |= StandardMaterialFlags::BASE_COLOR_TEXTURE;
|
||
}
|
||
if self.emissive_texture.is_some() {
|
||
flags |= StandardMaterialFlags::EMISSIVE_TEXTURE;
|
||
}
|
||
if self.metallic_roughness_texture.is_some() {
|
||
flags |= StandardMaterialFlags::METALLIC_ROUGHNESS_TEXTURE;
|
||
}
|
||
if self.occlusion_texture.is_some() {
|
||
flags |= StandardMaterialFlags::OCCLUSION_TEXTURE;
|
||
}
|
||
if self.double_sided {
|
||
flags |= StandardMaterialFlags::DOUBLE_SIDED;
|
||
}
|
||
if self.unlit {
|
||
flags |= StandardMaterialFlags::UNLIT;
|
||
}
|
||
if self.fog_enabled {
|
||
flags |= StandardMaterialFlags::FOG_ENABLED;
|
||
}
|
||
if self.depth_map.is_some() {
|
||
flags |= StandardMaterialFlags::DEPTH_MAP;
|
||
}
|
||
#[cfg(feature = "pbr_transmission_textures")]
|
||
{
|
||
if self.specular_transmission_texture.is_some() {
|
||
flags |= StandardMaterialFlags::SPECULAR_TRANSMISSION_TEXTURE;
|
||
}
|
||
if self.thickness_texture.is_some() {
|
||
flags |= StandardMaterialFlags::THICKNESS_TEXTURE;
|
||
}
|
||
if self.diffuse_transmission_texture.is_some() {
|
||
flags |= StandardMaterialFlags::DIFFUSE_TRANSMISSION_TEXTURE;
|
||
}
|
||
}
|
||
let has_normal_map = self.normal_map_texture.is_some();
|
||
if has_normal_map {
|
||
let normal_map_id = self.normal_map_texture.as_ref().map(|h| h.id()).unwrap();
|
||
if let Some(texture) = images.get(normal_map_id) {
|
||
match texture.texture_format {
|
||
// All 2-component unorm formats
|
||
TextureFormat::Rg8Unorm
|
||
| TextureFormat::Rg16Unorm
|
||
| TextureFormat::Bc5RgUnorm
|
||
| TextureFormat::EacRg11Unorm => {
|
||
flags |= StandardMaterialFlags::TWO_COMPONENT_NORMAL_MAP;
|
||
}
|
||
_ => {}
|
||
}
|
||
}
|
||
if self.flip_normal_map_y {
|
||
flags |= StandardMaterialFlags::FLIP_NORMAL_MAP_Y;
|
||
}
|
||
}
|
||
// NOTE: 0.5 is from the glTF default - do we want this?
|
||
let mut alpha_cutoff = 0.5;
|
||
match self.alpha_mode {
|
||
AlphaMode::Opaque => flags |= StandardMaterialFlags::ALPHA_MODE_OPAQUE,
|
||
AlphaMode::Mask(c) => {
|
||
alpha_cutoff = c;
|
||
flags |= StandardMaterialFlags::ALPHA_MODE_MASK;
|
||
}
|
||
AlphaMode::Blend => flags |= StandardMaterialFlags::ALPHA_MODE_BLEND,
|
||
AlphaMode::Premultiplied => flags |= StandardMaterialFlags::ALPHA_MODE_PREMULTIPLIED,
|
||
AlphaMode::Add => flags |= StandardMaterialFlags::ALPHA_MODE_ADD,
|
||
AlphaMode::Multiply => flags |= StandardMaterialFlags::ALPHA_MODE_MULTIPLY,
|
||
};
|
||
|
||
if self.attenuation_distance.is_finite() {
|
||
flags |= StandardMaterialFlags::ATTENUATION_ENABLED;
|
||
}
|
||
|
||
StandardMaterialUniform {
|
||
base_color: LinearRgba::from(self.base_color).to_f32_array().into(),
|
||
emissive: LinearRgba::from(self.emissive).to_f32_array().into(),
|
||
roughness: self.perceptual_roughness,
|
||
metallic: self.metallic,
|
||
reflectance: self.reflectance,
|
||
diffuse_transmission: self.diffuse_transmission,
|
||
specular_transmission: self.specular_transmission,
|
||
thickness: self.thickness,
|
||
ior: self.ior,
|
||
attenuation_distance: self.attenuation_distance,
|
||
attenuation_color: LinearRgba::from(self.attenuation_color)
|
||
.to_f32_array()
|
||
.into(),
|
||
flags: flags.bits(),
|
||
alpha_cutoff,
|
||
parallax_depth_scale: self.parallax_depth_scale,
|
||
max_parallax_layer_count: self.max_parallax_layer_count,
|
||
lightmap_exposure: self.lightmap_exposure,
|
||
max_relief_mapping_search_steps: self.parallax_mapping_method.max_steps(),
|
||
deferred_lighting_pass_id: self.deferred_lighting_pass_id as u32,
|
||
uv_transform: self.uv_transform.into(),
|
||
}
|
||
}
|
||
}
|
||
|
||
/// The pipeline key for [`StandardMaterial`].
|
||
#[derive(Clone, PartialEq, Eq, Hash)]
|
||
pub struct StandardMaterialKey {
|
||
normal_map: bool,
|
||
cull_mode: Option<Face>,
|
||
depth_bias: i32,
|
||
relief_mapping: bool,
|
||
diffuse_transmission: bool,
|
||
specular_transmission: bool,
|
||
}
|
||
|
||
impl From<&StandardMaterial> for StandardMaterialKey {
|
||
fn from(material: &StandardMaterial) -> Self {
|
||
StandardMaterialKey {
|
||
normal_map: material.normal_map_texture.is_some(),
|
||
cull_mode: material.cull_mode,
|
||
depth_bias: material.depth_bias as i32,
|
||
relief_mapping: matches!(
|
||
material.parallax_mapping_method,
|
||
ParallaxMappingMethod::Relief { .. }
|
||
),
|
||
diffuse_transmission: material.diffuse_transmission > 0.0,
|
||
specular_transmission: material.specular_transmission > 0.0,
|
||
}
|
||
}
|
||
}
|
||
|
||
impl Material for StandardMaterial {
|
||
fn fragment_shader() -> ShaderRef {
|
||
PBR_SHADER_HANDLE.into()
|
||
}
|
||
|
||
#[inline]
|
||
fn alpha_mode(&self) -> AlphaMode {
|
||
self.alpha_mode
|
||
}
|
||
|
||
#[inline]
|
||
fn opaque_render_method(&self) -> OpaqueRendererMethod {
|
||
match self.opaque_render_method {
|
||
// For now, diffuse transmission doesn't work under deferred rendering as we don't pack
|
||
// the required data into the GBuffer. If this material is set to `Auto`, we report it as
|
||
// `Forward` so that it's rendered correctly, even when the `DefaultOpaqueRendererMethod`
|
||
// is set to `Deferred`.
|
||
//
|
||
// If the developer explicitly sets the `OpaqueRendererMethod` to `Deferred`, we assume
|
||
// they know what they're doing and don't override it.
|
||
OpaqueRendererMethod::Auto if self.diffuse_transmission > 0.0 => {
|
||
OpaqueRendererMethod::Forward
|
||
}
|
||
other => other,
|
||
}
|
||
}
|
||
|
||
#[inline]
|
||
fn depth_bias(&self) -> f32 {
|
||
self.depth_bias
|
||
}
|
||
|
||
#[inline]
|
||
fn reads_view_transmission_texture(&self) -> bool {
|
||
self.specular_transmission > 0.0
|
||
}
|
||
|
||
fn prepass_fragment_shader() -> ShaderRef {
|
||
PBR_PREPASS_SHADER_HANDLE.into()
|
||
}
|
||
|
||
fn deferred_fragment_shader() -> ShaderRef {
|
||
PBR_SHADER_HANDLE.into()
|
||
}
|
||
|
||
#[cfg(feature = "meshlet")]
|
||
fn meshlet_mesh_fragment_shader() -> ShaderRef {
|
||
Self::fragment_shader()
|
||
}
|
||
|
||
#[cfg(feature = "meshlet")]
|
||
fn meshlet_mesh_prepass_fragment_shader() -> ShaderRef {
|
||
Self::prepass_fragment_shader()
|
||
}
|
||
|
||
#[cfg(feature = "meshlet")]
|
||
fn meshlet_mesh_deferred_fragment_shader() -> ShaderRef {
|
||
Self::deferred_fragment_shader()
|
||
}
|
||
|
||
fn specialize(
|
||
_pipeline: &MaterialPipeline<Self>,
|
||
descriptor: &mut RenderPipelineDescriptor,
|
||
_layout: &MeshVertexBufferLayoutRef,
|
||
key: MaterialPipelineKey<Self>,
|
||
) -> Result<(), SpecializedMeshPipelineError> {
|
||
if let Some(fragment) = descriptor.fragment.as_mut() {
|
||
let shader_defs = &mut fragment.shader_defs;
|
||
|
||
if key.bind_group_data.normal_map {
|
||
shader_defs.push("STANDARD_MATERIAL_NORMAL_MAP".into());
|
||
}
|
||
if key.bind_group_data.relief_mapping {
|
||
shader_defs.push("RELIEF_MAPPING".into());
|
||
}
|
||
|
||
if key.bind_group_data.diffuse_transmission {
|
||
shader_defs.push("STANDARD_MATERIAL_DIFFUSE_TRANSMISSION".into());
|
||
}
|
||
|
||
if key.bind_group_data.specular_transmission {
|
||
shader_defs.push("STANDARD_MATERIAL_SPECULAR_TRANSMISSION".into());
|
||
}
|
||
|
||
if key.bind_group_data.diffuse_transmission || key.bind_group_data.specular_transmission
|
||
{
|
||
shader_defs.push("STANDARD_MATERIAL_SPECULAR_OR_DIFFUSE_TRANSMISSION".into());
|
||
}
|
||
}
|
||
descriptor.primitive.cull_mode = key.bind_group_data.cull_mode;
|
||
if let Some(label) = &mut descriptor.label {
|
||
*label = format!("pbr_{}", *label).into();
|
||
}
|
||
if let Some(depth_stencil) = descriptor.depth_stencil.as_mut() {
|
||
depth_stencil.bias.constant = key.bind_group_data.depth_bias;
|
||
}
|
||
Ok(())
|
||
}
|
||
}
|