Simplify descriptor setup

Refs #1157

shaders/hlsl/shadowmappingcascade/depthpass.vert

@@ -1,4 +1,5 @@
 // Copyright 2020 Google LLC
+// Copyright 2024 Sascha Willems
 
 struct VSInput
 {
@@ -17,8 +18,7 @@ struct PushConsts {
 struct UBO  {
 	float4x4 cascadeViewProjMat[SHADOW_MAP_CASCADE_COUNT];
 };
-
-cbuffer ubo : register(b0) { UBO ubo; }
+cbuffer ubo : register(b3) { UBO ubo; }
 
 struct VSOutput
 {

shaders/hlsl/shadowmappingcascade/scene.frag

@@ -1,4 +1,5 @@
 // Copyright 2020 Google LLC
+// Copyright 2024 Sascha Willems
 
 #define SHADOW_MAP_CASCADE_COUNT 4
 
@@ -22,7 +23,6 @@ struct VSOutput
 
 struct UBO {
 	float4 cascadeSplits;
-	float4x4 cascadeViewProjMat[SHADOW_MAP_CASCADE_COUNT];
 	float4x4 inverseViewMat;
 	float3 lightDir;
 	float _pad;
@@ -30,6 +30,11 @@ struct UBO {
 };
 cbuffer ubo : register(b2) { UBO ubo; };
 
+struct CVPM  {
+	float4x4 matrices[SHADOW_MAP_CASCADE_COUNT];
+};
+cbuffer cascadeViewProjMatrices : register(b3) { CVPM cascadeViewProjMatrices; }
+
 static const float4x4 biasMat = float4x4(
 	0.5, 0.0, 0.0, 0.5,
 	0.0, 0.5, 0.0, 0.5,
@@ -90,7 +95,7 @@ float4 main(VSOutput input) : SV_TARGET
 	}
 
 	// Depth compare for shadowing
-	float4 shadowCoord = mul(biasMat, mul(ubo.cascadeViewProjMat[cascadeIndex], float4(input.Pos, 1.0)));
+	float4 shadowCoord = mul(biasMat, mul(cascadeViewProjMatrices.matrices[cascadeIndex], float4(input.Pos, 1.0)));
 
 	float shadow = 0;
 	if (enablePCF == 1) {