forked from joejulian/gio
Elias Naur
1062d4e79d
Safari's WebGL1 implementation (rightly) complains that first-class array types are not supported as function result types. Define and use a struct type instead. While we're here, use const variables instead of functions. Signed-off-by: Elias Naur <mail@eliasnaur.com>
52 lines
1.1 KiB
C++
52 lines
1.1 KiB
C++
// SPDX-License-Identifier: Unlicense OR MIT
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struct m3x2 {
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vec3 r0;
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vec3 r1;
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};
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// fboTextureTransform is the transformation
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// that cancels the implied transformation between
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// the framebuffer and its texture.
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// Only two rows are returned. The last is implied
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// to be [0, 0, 1].
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const m3x2 fboTextureTransform = m3x2(
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#ifdef HLSL
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vec3(1.0, 0.0, 0.0),
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vec3(0.0, -1.0, 1.0)
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#else
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vec3(1.0, 0.0, 0.0),
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vec3(0.0, 1.0, 0.0)
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#endif
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);
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// fboTransform is the transformation
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// that cancels the implied transformation between
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// the clip space and the framebuffer.
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// Only two rows are returned. The last is implied
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// to be [0, 0, 1].
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const m3x2 fboTransform = m3x2(
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#ifdef HLSL
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vec3(1.0, 0.0, 0.0),
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vec3(0.0, 1.0, 0.0)
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#else
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vec3(1.0, 0.0, 0.0),
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vec3(0.0, -1.0, 0.0)
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#endif
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);
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// toClipSpace converts an OpenGL gl_Position value to a
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// native GPU position.
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vec4 toClipSpace(vec4 pos) {
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#ifdef HLSL
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// Map depths to the Direct3D [0; 1] range.
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return vec4(pos.xy, (pos.z + pos.w)*.5, pos.w);
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#else
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return pos;
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#endif
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}
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vec3 transform3x2(m3x2 t, vec3 v) {
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return vec3(dot(t.r0, v), dot(t.r1, v), dot(vec3(0.0, 0.0, 1.0), v));
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}
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