4ecbe001d5
# Objective - It's currently very hard for beginners and advanced users to get a full understanding of a complete render phase. ## Solution - Implement a full custom render phase - The render phase in the example is intended to show a custom stencil phase that renders the stencil in red directly on the screen --- ## Showcase <img width="1277" alt="image" src="https://github.com/user-attachments/assets/e9dc0105-4fb6-463f-ad53-0529b575fd28" /> ## Notes More docs to explain what is going on is still needed but the example works and can already help some people. We might want to consider using a batched phase and cold specialization in the future, but the example is already complex enough as it is. --------- Co-authored-by: Christopher Biscardi <chris@christopherbiscardi.com>
42 lines
1.5 KiB
WebGPU Shading Language
42 lines
1.5 KiB
WebGPU Shading Language
//! A shader showing how to use the vertex position data to output the
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//! stencil in the right position
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// First we import everything we need from bevy_pbr
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// A 2d shader would be vevry similar but import from bevy_sprite instead
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#import bevy_pbr::{
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mesh_functions,
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view_transformations::position_world_to_clip
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}
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struct Vertex {
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// This is needed if you are using batching and/or gpu preprocessing
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// It's a built in so you don't need to define it in the vertex layout
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@builtin(instance_index) instance_index: u32,
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// Like we defined for the vertex layout
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// position is at location 0
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@location(0) position: vec3<f32>,
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};
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// This is the output of the vertex shader and we also use it as the input for the fragment shader
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struct VertexOutput {
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@builtin(position) clip_position: vec4<f32>,
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@location(0) world_position: vec4<f32>,
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};
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@vertex
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fn vertex(vertex: Vertex) -> VertexOutput {
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var out: VertexOutput;
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// This is how bevy computes the world position
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// The vertex.instance_index is very important. Especially if you are using batching and gpu preprocessing
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var world_from_local = mesh_functions::get_world_from_local(vertex.instance_index);
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out.world_position = mesh_functions::mesh_position_local_to_world(world_from_local, vec4(vertex.position, 1.0));
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out.clip_position = position_world_to_clip(out.world_position.xyz);
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return out;
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}
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@fragment
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fn fragment(in: VertexOutput) -> @location(0) vec4<f32> {
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// Output a red color to represent the stencil of the mesh
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return vec4(1.0, 0.0, 0.0, 1.0);
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}
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