random offsets in raygen

raytracer/ray_tracing_gltf/hello_vulkan.cpp

@@ -351,22 +351,21 @@ void HelloVulkan::createPointsetTexture(const VkCommandBuffer& cmdBuf)
 
   // TODO: generate and parse pointset here
   std::vector<float_t> points{};
-  points.reserve(swapchainExtent.height * swapchainExtent.width * 2);
+  points.reserve(swapchainExtent.height * swapchainExtent.width * 2 * 4);
 
-  for(int y = 0; y < swapchainExtent.height; ++y)
+  for(int y = 0; y < swapchainExtent.height * 4; ++y)
   {
     for(int x = 0; x < swapchainExtent.width; ++x)
     {
       float rand_x = static_cast<float>(rand()) / static_cast<float_t>(RAND_MAX);
       float rand_y = static_cast<float>(rand()) / static_cast<float_t>(RAND_MAX);
-      std::cout << "x: " << rand_x << "|y: " << rand_y << std::endl;
-      points.emplace_back(rand_x);
-      points.emplace_back(rand_y);
+      points.push_back(rand_x);
+      points.push_back(rand_y);
     }
   }
 
-
-  VkImageCreateInfo imageCreateInfo = nvvk::makeImage2DCreateInfo(swapchainExtent, VK_FORMAT_R32G32_SFLOAT, VK_IMAGE_USAGE_SAMPLED_BIT, false);
+  VkImageCreateInfo imageCreateInfo =
+      nvvk::makeImage2DCreateInfo(swapchainExtent, VK_FORMAT_R32G32_SFLOAT, VK_IMAGE_USAGE_SAMPLED_BIT, false);
   nvvk::Image           image  = m_alloc.createImage(cmdBuf, points.size(), points.data(), imageCreateInfo);
   VkImageViewCreateInfo ivInfo = nvvk::makeImageViewCreateInfo(image.image, imageCreateInfo);
   m_pointset                   = m_alloc.createTexture(image, ivInfo, samplerCreateInfo);

raytracer/ray_tracing_gltf/main.cpp

@@ -71,8 +71,8 @@ void renderUI(HelloVulkan& helloVk, bool useRaytracer)
 //////////////////////////////////////////////////////////////////////////
 //////////////////////////////////////////////////////////////////////////
 //////////////////////////////////////////////////////////////////////////
-static int const SAMPLE_WIDTH  = 1280;
-static int const SAMPLE_HEIGHT = 720;
+static int const SAMPLE_WIDTH  = 800;
+static int const SAMPLE_HEIGHT = 800;
 
 
 //--------------------------------------------------------------------------------------------------

raytracer/ray_tracing_gltf/shaders/raytrace.rgen

@@ -40,8 +40,10 @@ layout(set = 1, binding = ePointsetTexture) uniform sampler2D pointset; // bluen
 
 void main()
 {
-  const vec2 pixelCenter = vec2(gl_LaunchIDEXT.xy) + vec2(0.5);
-  const vec2 inUV        = pixelCenter / vec2(gl_LaunchSizeEXT.xy);
+    vec2 uv = vec2(float(gl_LaunchIDEXT.x) / float(gl_LaunchSizeEXT.x), float(gl_LaunchIDEXT.y) / float(gl_LaunchSizeEXT.y));
+
+    const vec2 rayOriginInPix = vec2(gl_LaunchIDEXT.xy) + texture(pointset, uv).xy;
+    const vec2 inUV        = rayOriginInPix / vec2(gl_LaunchSizeEXT.xy);
     vec2       d           = inUV * 2.0 - 1.0;
 
     vec4 origin    = uni.viewInverse * vec4(0, 0, 0, 1);
@@ -65,7 +67,5 @@ void main()
     0// payload (location = 0)
     );
 
-    //imageStore(image, ivec2(gl_LaunchIDEXT.xy), vec4(prd.hitValue, 1.0));
-    vec2 uv = vec2(float(gl_LaunchIDEXT.x) / float(gl_LaunchSizeEXT.x) - 0.5, float(gl_LaunchIDEXT.y) / float(gl_LaunchSizeEXT.y) - 0.5);
-    imageStore(image, ivec2(gl_LaunchIDEXT.xy), texture(pointset, uv));
+    imageStore(image, ivec2(gl_LaunchIDEXT.xy), vec4(prd.hitValue, 1.0));
 }