quakeforge/libs/video/renderer/vulkan/shader/bsp_sky.frag
Bill Currie a08261c620 [vulkan] Use a buffer for entity transform and color data
This allows the use of an entity id to index into the entity data and
fetch the transform and colormod data in the vertex shader, thus making
instanced rendering possible. Non-world brush entities are still not
rendered, but the world entity is using both the entity data buffer and
entid buffer.
2022-05-25 00:17:57 +09:00

97 lines
2.2 KiB
GLSL

#version 450
layout (constant_id = 0) const bool doSkyBox = false;
layout (constant_id = 1) const bool doSkySheet = false;
layout (set = 2, binding = 0) uniform sampler2DArray SkySheet;
layout (set = 3, binding = 0) uniform samplerCube SkyBox;
layout (push_constant) uniform PushConstants {
vec4 fog;
float time;
float alpha;
};
layout (location = 0) in vec4 tl_st;
layout (location = 1) in vec3 direction;
layout (location = 0) out vec4 frag_color;
const float SCALE = 189.0 / 64.0;
vec4
fogBlend (vec4 color)
{
float az = fog.a * gl_FragCoord.z / gl_FragCoord.w;
vec3 fog_color = fog.rgb;
float fog_factor = exp (-az * az);
return vec4 (mix (fog_color.rgb, color.rgb, fog_factor), color.a);
}
vec4
sky_sheet (vec3 dir, float time)
{
float len;
vec2 flow = vec2 (1.0, 1.0);
vec2 base;
vec3 st1, st2;
vec4 c1, c2, c;
dir.z *= 3.0;
len = dot (dir, dir);
len = SCALE * inversesqrt (len);
base = dir.yx * vec2(1.0, -1.0) * len;
st1 = vec3 (base + flow * time / 8.0, 0);
st2 = vec3 (base + flow * time / 16.0, 1);
c1 = texture (SkySheet, st1);
c2 = texture (SkySheet, st2);
c = vec4 (mix (c2.rgb, c1.rgb, c1.a), max (c1.a, c2.a));
return c;
}
vec4
sky_box (vec3 dir, float time)
{
// NOTE: quake's world is right-handed with Z up and X forward, but
// Vulkan's cube maps are left-handed with Y up and Z forward. The
// rotation to X foward is done by the Sky matrix so all that's left
// to do here is swizzle the Y and Z coordinates
dir = normalize(dir);
//return vec4(dir.xyz, 1) * 0.5 + vec4(0.5);
return texture (SkyBox, dir.xzy);
}
vec4
sky_color (vec3 dir, float time)
{
if (!doSkySheet) {
return sky_box (dir, time);
} if (!doSkyBox) {
return sky_sheet (dir, time);
} else {
// can see through the sheet (may look funny when looking down)
// maybe have 4 sheet layers instead of 2?
vec4 c1 = sky_sheet (dir, time);
vec4 c2 = sky_box (dir, time);
return vec4 (mix (c2.rgb, c1.rgb, c1.a), max (c1.a, c2.a));
return vec4 (1, 0, 1, 1);
}
}
void
main (void)
{
vec4 c;
if (doSkyBox || doSkySheet) {
c = sky_color (direction, time);
} else {
c = vec4 (0, 0, 0, 1);
}
frag_color = c;//fogBlend (c);
}