feat: add click to select

destrum/src/Graphics/Pipelines/MeshPipeline.cpp

@@ -21,7 +21,8 @@ void MeshPipeline::init(
     GfxDevice& gfxDevice,
     RenderResources& resources,
     VkFormat drawImageFormat,
-    VkFormat depthImageFormat)
+    VkFormat depthImageFormat,
+    VkFormat selectionImageFormat)
 {
     try
     {
@@ -31,6 +32,9 @@ void MeshPipeline::init(
         const auto fragShader =
             AssetFS::GetInstance().GetCookedPathForFile("engine://shaders/mesh.frag");
 
+        const auto selectionShader =
+            AssetFS::GetInstance().GetCookedPathForFile("engine://shaders/selection.frag");
+
         const auto bufferRange = VkPushConstantRange{
             .stageFlags = VK_SHADER_STAGE_VERTEX_BIT | VK_SHADER_STAGE_FRAGMENT_BIT,
             .offset = 0,
@@ -82,6 +86,27 @@ void MeshPipeline::init(
             );
         }
 
+        {
+            PipelineConfigInfo pipelineConfig{};
+            Pipeline::DefaultPipelineConfigInfo(pipelineConfig);
+
+            pipelineConfig.name = "Mesh Selection Prepass Pipeline";
+            pipelineConfig.pipelineLayout = m_pipelineLayout;
+
+            pipelineConfig.vertexAttributeDescriptions = {};
+            pipelineConfig.vertexBindingDescriptions = {};
+
+            pipelineConfig.colorAttachments = {selectionImageFormat};
+            pipelineConfig.depthAttachment = depthImageFormat;
+
+            m_selectionPrepassPipeline = std::make_unique<Pipeline>(
+                gfxDevice,
+                vertexShader.string(),
+                selectionShader.string(),
+                pipelineConfig
+            );
+        }
+
         {
             PipelineConfigInfo pipelineConfig{};
             Pipeline::DefaultPipelineConfigInfo(pipelineConfig);
@@ -120,16 +145,18 @@ void MeshPipeline::drawDepthPrepass(
     const RenderResources& resources,
     const GPUBuffer& sceneDataBuffer,
     const IndirectDrawList& drawList,
-    const IndirectDrawList::View& view)
+    const IndirectDrawList::View& view,
+    bool writeObjectIds)
 {
-    if (!m_depthPrepassPipeline)
+    const auto& pipeline = writeObjectIds ? m_selectionPrepassPipeline : m_depthPrepassPipeline;
+    if (!pipeline)
     {
         return;
     }
 
     drawMeshes(
         cmd,
-        *m_depthPrepassPipeline,
+        *pipeline,
         renderExtent,
         resources,
         sceneDataBuffer,
@@ -228,6 +255,7 @@ void MeshPipeline::cleanup(VkDevice device)
 {
     m_pipeline.reset();
     m_depthPrepassPipeline.reset();
+    m_selectionPrepassPipeline.reset();
 
     if (m_pipelineLayout != VK_NULL_HANDLE && device != VK_NULL_HANDLE)
     {