Use non-uniform indexing to access textures

Author: SaschaWillems

samples/extensions/descriptor_heap/descriptor_heap.cpp

@@ -26,6 +26,7 @@ DescriptorHeap::DescriptorHeap()
 	add_device_extension(VK_KHR_DYNAMIC_RENDERING_EXTENSION_NAME);
 	add_device_extension(VK_KHR_MAINTENANCE_5_EXTENSION_NAME);
 	add_device_extension(VK_EXT_DESCRIPTOR_HEAP_EXTENSION_NAME);
+	add_device_extension(VK_EXT_DESCRIPTOR_INDEXING_EXTENSION_NAME);
 }
 
 DescriptorHeap::~DescriptorHeap()
@@ -73,6 +74,8 @@ void DescriptorHeap::request_gpu_features(vkb::core::PhysicalDeviceC &gpu)
 
 	// We need to enable the descriptor heap feature to make use of them
 	REQUEST_REQUIRED_FEATURE(gpu, VkPhysicalDeviceDescriptorHeapFeaturesEXT, descriptorHeap);
+	// The way we index inside the shader also requires use of non-uniform indexing
+	REQUEST_REQUIRED_FEATURE(gpu, VkPhysicalDeviceDescriptorIndexingFeaturesEXT, shaderSampledImageArrayNonUniformIndexing);
 
 	if (gpu.get_features().samplerAnisotropy)
 	{

shaders/descriptor_heap/glsl/cube.frag

@@ -16,6 +16,8 @@
  * limitations under the License.
  */
 
+#extension GL_EXT_nonuniform_qualifier : require
+
 layout (set = 1, binding = 0) uniform texture2D textureImage[2];
 layout (set = 2, binding = 0) uniform sampler textureSampler[2];
 
@@ -31,5 +33,5 @@ layout (location = 0) out vec4 outFragColor;
 
 void main() 
 {
-	outFragColor = texture(sampler2D(textureImage[inInstanceIndex], textureSampler[pushConsts.samplerIndex]), inUV);
+	outFragColor = texture(sampler2D(textureImage[nonuniformEXT(inInstanceIndex)], textureSampler[pushConsts.samplerIndex]), inUV);
 }

shaders/descriptor_heap/glsl/cube.frag.spv

@@ -36,5 +36,5 @@ struct PushConsts
 
 float4 main(VSOutput input) : SV_TARGET0
 {
-    return textureImage[input.InstanceIndex].Sample(textureSampler[pushConsts.samplerIndex], input.UV);
+    return textureImage[NonUniformResourceIndex(input.InstanceIndex)].Sample(textureSampler[pushConsts.samplerIndex], input.UV);
 }

shaders/descriptor_heap/hlsl/cube.frag.hlsl

@@ -28,5 +28,5 @@ struct VSOutput
 [shader("fragment")]
 float4 main(VSOutput input, uniform int samplerIndex, uniform int frameIndex)
 {
-    return textureImage[input.InstanceIndex].Sample(textureSampler[samplerIndex], input.UV);
+    return textureImage[NonUniformResourceIndex(input.InstanceIndex)].Sample(textureSampler[samplerIndex], input.UV);
 }