Files
LNXSDK/leenkx/Shaders/include/pass_viewray.vert.glsl
2025-04-29 14:33:13 -06:00

32 lines
708 B
GLSL

#version 450
#include "compiled.inc"
uniform mat4 invVP;
uniform vec3 eye;
in vec2 pos;
out vec2 texCoord;
out vec3 viewRay;
void main() {
// Scale vertex attribute to [0-1] range
const vec2 madd = vec2(0.5, 0.5);
texCoord = pos.xy * madd + madd;
#ifdef _InvY
texCoord.y = 1.0 - texCoord.y;
#endif
gl_Position = vec4(pos.xy, 0.0, 1.0);
// fullscreen triangle: http://de.slideshare.net/DevCentralAMD/vertex-shader-tricks-bill-bilodeau
// gl_Position = vec4((gl_VertexID % 2) * 4.0 - 1.0, (gl_VertexID / 2) * 4.0 - 1.0, 0.0, 1.0);
// For reverse-Z, the “far” plane lives at NDC z = 0
vec4 v = vec4(pos.x, pos.y, 0.0, 1.0);
v = vec4(invVP * v);
v.xyz /= v.w;
viewRay = v.xyz - eye;
}