Add vk_ray_trace_indirect_scissor sample

ray_tracing_indirect_scissor/shaders/raytrace.rgen

@@ -0,0 +1,71 @@
+#version 460
+#extension GL_EXT_ray_tracing : require
+#extension GL_GOOGLE_include_directive : enable
+#include "raycommon.glsl"
+
+layout(binding = 0, set = 0) uniform accelerationStructureEXT topLevelAS;
+layout(binding = 1, set = 0, rgba32f) uniform image2D image;
+
+layout(location = 0) rayPayloadEXT hitPayload prd;
+
+layout(binding = 0, set = 1) uniform CameraProperties
+{
+  mat4 view;
+  mat4 proj;
+  mat4 viewInverse;
+  mat4 projInverse;
+}
+cam;
+
+layout(binding = 2, set = 0) buffer LanternArray { LanternIndirectEntry lanterns[]; } lanterns;
+
+void main()
+{
+  // Global light pass is a full screen rectangle (lower corner 0,0), but
+  // lantern passes are only run within rectangles that may be offset.
+  ivec2 pixelOffset = ivec2(0);
+  if (pushC.lanternPassNumber >= 0)
+  {
+    pixelOffset.x = lanterns.lanterns[pushC.lanternPassNumber].offsetX;
+    pixelOffset.y = lanterns.lanterns[pushC.lanternPassNumber].offsetY;
+  }
+
+  const ivec2 pixelIntCoord = ivec2(gl_LaunchIDEXT.xy) + pixelOffset;
+  const vec2 pixelCenter = vec2(pixelIntCoord) + vec2(0.5);
+  const vec2 inUV        = pixelCenter / vec2(pushC.screenX, pushC.screenY);
+  vec2       d           = inUV * 2.0 - 1.0;
+
+  vec4 origin    = cam.viewInverse * vec4(0, 0, 0, 1);
+  vec4 target    = cam.projInverse * vec4(d.x, d.y, 1, 1);
+  vec4 direction = cam.viewInverse * vec4(normalize(target.xyz), 0);
+
+  uint  rayFlags = gl_RayFlagsOpaqueEXT;
+  float tMin     = 0.001;
+  float tMax     = 10000.0;
+
+  // Lanterns (self-illuminating) and miss shader (constant background color)
+  // do not use additive blending. Only normal OBJ geometry is additive,
+  // OBJ closest hit sets this to true.
+  prd.additiveBlending = false;
+
+  traceRayEXT(topLevelAS,     // acceleration structure
+              rayFlags,       // rayFlags
+              0xFF,           // cullMask
+              0,              // sbtRecordOffset
+              0,              // sbtRecordStride
+              0,              // missIndex
+              origin.xyz,     // ray origin
+              tMin,           // ray min range
+              direction.xyz,  // ray direction
+              tMax,           // ray max range
+              0               // payload (location = 0)
+  );
+
+  // Either add to or replace output image color based on prd.additiveBlending.
+  // Global pass always replaces color as it is the first pass.
+  vec3 oldColor = vec3(0);
+  if (prd.additiveBlending && pushC.lanternPassNumber >= 0) {
+    oldColor = imageLoad(image, pixelIntCoord).rgb;
+  }
+  imageStore(image, pixelIntCoord, vec4(prd.hitValue + oldColor, 1.0));
+}