Files
Destrum/destrum/assets_src/shaders/skybox.frag
2026-01-21 06:05:35 +01:00

36 lines
1.1 KiB
GLSL

#version 450
#extension GL_GOOGLE_include_directive : require
#extension GL_EXT_nonuniform_qualifier : enable
#include "bindless.glsl"
layout(location = 0) in vec2 uv; // from fullscreen triangle: 0..2 range
layout(location = 0) out vec4 outColor;
layout(push_constant) uniform SkyboxPC {
mat4 invViewProj; // inverse(Proj * View) (your current setup)
vec4 cameraPos; // xyz = camera world position
uint skyboxTextureId; // index into textureCubes[]
} pcs;
void main()
{
// Fullscreen-triangle trick gives uv in [0..2]. Convert to [0..1].
vec2 uv01 = uv * 0.5;
// Build an NDC point on the far plane.
// Vulkan NDC is x,y in [-1..1], z in [0..1]. Using z=1 means "far".
vec4 ndc = vec4(uv01 * 2.0 - 1.0, 1.0, 1.0);
// Unproject to world space
vec4 world = pcs.invViewProj * ndc;
vec3 worldPos = world.xyz / world.w;
// Direction from camera through this pixel
vec3 dir = normalize(worldPos - pcs.cameraPos.xyz);
// Sample cubemap directly
outColor = sampleTextureCubeLinear(pcs.skyboxTextureId, dir);
// outColor = sampleTextureCubeNearest(pcs.skyboxTextureId, dir);
}