SlangをColumnMajorに変更

Author: yknishidate

sample/hello_raytracing/main.cpp

@@ -115,7 +115,7 @@ class HelloApp : public App {
                                  vk::ImageLayout::ePresentSrcKHR);
     }
 
-    std::vector<Vertex> m_vertices{{{-1, 0, 0}}, {{0, -1, 0}}, {{1, 0, 0}}};
+    std::vector<Vertex> m_vertices{{{-1, 0, 0}}, {{0, 1, 0}}, {{1, 0, 0}}};
     std::vector<uint32_t> m_indices{0, 1, 2};
     Mesh m_mesh;
 

sample/hello_raytracing/shaders.slang

@@ -16,19 +16,25 @@ struct RayPayload
     float3 color;
 };
 
+float2 PixelToScreen(uint2 launchID, uint2 launchSize)
+{
+    float2 screen = ((float2(launchID.xy) + float2(0.5f)) / float2(launchSize.xy)) * 2.0f - 1.0f;
+    return { screen.x, -screen.y };
+}
+
 [shader("raygeneration")]
 void rayGenMain()
 {
     uint3 launchID   = DispatchRaysIndex();
     uint3 launchSize = DispatchRaysDimensions();
 
     // 画面上のUV座標を [(-1) .. (+1)] にマッピング
-    float2 uv = (float2(launchID.xy) / float2(launchSize.xy)) * 2.0f - 1.0f;
+    float2 screen = PixelToScreen(launchID.xy, launchSize.xy);
 
     // 逆行列を使ってワールド座標系でのレイを生成
-    float4 origin = mul(float4(0, 0, 0, 1), gPush.invView);
-    float4 target = mul(float4(uv.x, uv.y, 1.0f, 1.0f), gPush.invProj);
-    float4 direction = mul(float4(normalize(target.xyz), 0), gPush.invView);
+    float4 origin = mul(gPush.invView, float4(0, 0, 0, 1));
+    float4 target = mul(gPush.invProj, float4(screen.xy, 1.0f, 1.0f));
+    float4 direction = mul(gPush.invView, float4(normalize(target.xyz), 0));
 
     // Ray Payload 初期化
     RayPayload payload;

src/Compiler/Compiler.cpp

@@ -62,6 +62,7 @@ std::vector<Slang::ComPtr<slang::IBlob>> SlangCompiler::compileShaders(const std
     sessionDesc.targetCount = 1;
     sessionDesc.compilerOptionEntries = options.data();
     sessionDesc.compilerOptionEntryCount = (uint32_t)options.size();
+    sessionDesc.defaultMatrixLayoutMode = SLANG_MATRIX_LAYOUT_COLUMN_MAJOR;
 
     Slang::ComPtr<slang::ISession> session;
     ASSERT_ON_SLANG_FAIL(m_globalSession->createSession(sessionDesc, session.writeRef()));