41 lines
900 B
Plaintext
41 lines
900 B
Plaintext
// Pick a frame of a sprite animation from an instance.
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fn animate(sprite_index: u32, age: f32, offset: f32) -> f32 {
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let len = global_sprites[sprite_index].frame_count;
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let rep = global_sprites[sprite_index].repeatmode;
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let fps = global_sprites[sprite_index].fps;
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var frame: f32 = 0.0;
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// Once
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if rep == u32(1) {
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frame = min(
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age / fps + offset,
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f32(len) - 1.0
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);
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// Reverse
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} else if rep == u32(2) {
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let x = age / fps + offset;
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let m = f32(len) * 2.0 - 1.0;
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// x fmod m
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frame = x - floor(x / m) * m;
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if frame >= f32(len) {
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frame = (
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f32(len) + f32(len) - 1.0
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// Split integer and fractional part so tweening works properly
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- floor(frame)
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+ fract(frame)
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);
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}
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// Repeat (default)
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} else {
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let x = age / fps + offset;
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let m = f32(len);
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frame = x - floor(x / m) * m;
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}
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return frame + f32(global_sprites[sprite_index].first_frame);
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} |