20 lines
510 B
Rust
20 lines
510 B
Rust
use crate::{Mat4, Vec3};
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pub trait FaceToward {
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fn face_toward(eye: Vec3, center: Vec3, up: Vec3) -> Self;
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}
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impl FaceToward for Mat4 {
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fn face_toward(eye: Vec3, center: Vec3, up: Vec3) -> Self {
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let forward = (center - eye).normalize();
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let right = up.cross(forward).normalize();
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let up = forward.cross(right);
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Mat4::from_cols(
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right.extend(0.0),
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up.extend(0.0),
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forward.extend(0.0),
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eye.extend(1.0),
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)
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}
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}
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