Fix alignment computation for `std140` uniforms

Fixes #55

I was incorrectly computing alignment as `elementSize * elementAlignment`, rounded up to a power of two (which works out to be `elementSize` squared), when I should have been using `elementSize * elementCount`, rounded up to a power of two.

1 files changed, 3 insertions, 2 deletions

diff --git a/source/slang/type-layout.cpp b/source/slang/type-layout.cpp
index 2fcf64226..fbaec3736 100644
--- a/source/slang/type-layout.cpp
+++ b/source/slang/type-layout.cpp
@@ -163,10 +163,11 @@ struct Std140LayoutRulesImpl : GLSLConstantBufferLayoutRulesImpl
     SimpleLayoutInfo GetVectorLayout(SimpleLayoutInfo elementInfo, size_t elementCount) override
     {
         assert(elementInfo.kind == LayoutResourceKind::Uniform);
+        auto size = elementInfo.size * elementCount;
         SimpleLayoutInfo vectorInfo(
             LayoutResourceKind::Uniform,
-            elementInfo.size * elementCount,
-            RoundUpToPowerOfTwo(elementInfo.size * elementInfo.alignment));
+            size,
+            RoundUpToPowerOfTwo(size));
         return vectorInfo;
     }
 };