SourceTermAnalysisSystem_vue/node_modules/@cesium/engine/Source/Shaders/Voxels/IntersectDepth.glsl
2026-05-15 10:22:44 +08:00

31 lines
1.1 KiB
GLSL

// See IntersectionUtils.glsl for the definitions of Ray, Intersections,
// setIntersectionPair, INF_HIT, NO_HIT
/* intersectDepth defines (set in Scene/VoxelRenderResources.js)
#define DEPTH_INTERSECTION_INDEX ###
*/
uniform mat4 u_transformPositionViewToUv;
void intersectDepth(in vec2 screenCoord, in Ray ray, inout Intersections ix) {
float logDepthOrDepth = czm_unpackDepth(texture(czm_globeDepthTexture, screenCoord));
float entry;
float exit;
if (logDepthOrDepth != 0.0) {
// Calculate how far the ray must travel before it hits the depth buffer.
vec4 eyeCoordinateDepth = czm_screenToEyeCoordinates(screenCoord, logDepthOrDepth);
eyeCoordinateDepth /= eyeCoordinateDepth.w;
vec3 depthPositionUv = vec3(u_transformPositionViewToUv * eyeCoordinateDepth);
entry = dot(depthPositionUv - ray.pos, ray.dir);
exit = +INF_HIT;
} else {
// There's no depth at this location.
entry = NO_HIT;
exit = NO_HIT;
}
ix.distanceToDepthBuffer = entry;
#if defined(DEPTH_TEST)
setIntersectionPair(ix, DEPTH_INTERSECTION_INDEX, vec2(entry, exit));
#endif
}