65 lines
1.2 KiB
GLSL
65 lines
1.2 KiB
GLSL
#version 460 core
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layout (location = 0) in vec3 norm;
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layout (location = 1) in vec2 texCoord;
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layout (location = 0) out vec4 FragColor;
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layout (set = 0, binding = 0) uniform Matrices {
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mat4 mvp;
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float time;
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float aspect_ratio;
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};
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/* 4-float alignment in memory*/
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struct Ray {
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vec3 orig;
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float min;
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vec3 dir;
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float max;
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};
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vec3 ray_color(vec3 ray) {
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float a = 0.5 * (ray.y+1.0);
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return vec3(1.0-a) + a*vec3(0.5, 0.7, 1.0);
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}
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/* returns float of where you hit, or -1.0 */
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float sphere(vec3 center, float r, Ray ray) {
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vec3 p = ray.orig-center;
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float a = dot(ray.dir, ray.dir);
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float half_b = dot(p, ray.dir);
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float c = dot(p, p) - r*r;
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float discr = half_b*half_b - a*c;
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if(discr < 0.0)
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return -1.0;
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return -half_b-sqrt(discr)/a;
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}
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void main() {
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vec2 pixel = texCoord*2.0-1.0;
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Ray ray;
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ray.orig = vec3(0.0);
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ray.min = 0.1;
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ray.max = 10000.0;
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float fov = radians(90);
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ray.dir = normalize(vec3(pixel.x * aspect_ratio, pixel.y, tan(fov/2.0)));
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vec3 sphere_center = vec3(0.0, 0.0, 1.0);
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float d = sphere(sphere_center, 0.5, ray);
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FragColor = vec4(texCoord, 1.0, 1.0);
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return;
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if(d < 0.0) {
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FragColor = vec4(0.0);
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return;
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}
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vec3 n = normalize(ray.dir*d-sphere_center);
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FragColor = vec4((n+vec3(1.0)) / 2.0, 1.0);
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} |