Added overloaded operators in Slang to match GLSL matrix operations

Author: corporateshark

lvk/vulkan/VulkanClasses.cpp

@@ -5840,6 +5840,14 @@ lvk::ShaderModuleState lvk::VulkanContext::createShaderModuleFromSlang(ShaderSta
     }
   };
 
+  // overloaded operators to mimic GLSL matrix operations
+  sourcePatched +=
+      "float2x2 operator*(float2x2 a, float2x2 b) { return mul(b, a); }\n"
+      "float2   operator*(float2x2 a, float2   b) { return mul(b, a); }\n"
+      "float3x3 operator*(float3x3 a, float3x3 b) { return mul(b, a); }\n"
+      "float3   operator*(float3x3 a, float3   b) { return mul(b, a); }\n"
+      "float4x4 operator*(float4x4 a, float4x4 b) { return mul(b, a); }\n"
+      "float4   operator*(float4x4 a, float4   b) { return mul(b, a); }\n";
   // bindless texture and sampler arrays
   sourcePatched +=
       "[[vk::binding(0, 0)]] Texture2D    kTextures2D[];\n"

samples/002_RenderToCubeMap.cpp

@@ -113,7 +113,7 @@ static const float3 vertices[8] = {
 VertexStageOutput vertexMain(uint vertexID : SV_VertexID) {
   VertexStageOutput out;
   float3 v = vertices[vertexID];
-  out.sv_Position = mul(float4(v, 1.0), pc.mvp);
+  out.sv_Position = pc.mvp * float4(v, 1.0);
   out.dir = v;
   out.textureId = pc.texture0;
   return out;

samples/003_RenderToCubeMapSinglePass.cpp

@@ -111,7 +111,7 @@ static const float3 vertices[8] = {
 VertexStageOutput vertexMain(uint vertexID : SV_VertexID) {
   VertexStageOutput out;
   float3 v = vertices[vertexID];
-  out.sv_Position = mul(float4(v, 1.0), pc.mvp);
+  out.sv_Position = pc.mvp * float4(v, 1.0);
   out.dir = v;
   out.textureId = pc.texture0;
   return out;

samples/009_TriplanarMapping.cpp

@@ -64,7 +64,7 @@ VertexStageOutput vertexMain(uint vertexID   : SV_VertexID,
 
   VertexStageOutput out;
 
-  out.sv_Position = mul(float4(v.x, v.y, v.z, 1.0), mul(model, mul(view, proj)));
+  out.sv_Position = proj * view * model * float4(v.x, v.y, v.z, 1.0);
   out.color = float3(v.r, v.g, v.b);
   out.normal = normalize(float3(v.x, v.y, v.z)); // object space normal
 

samples/RTX_001_Hello.cpp

@@ -36,9 +36,9 @@ void rayGenMain() {
   float2 pixelCenter = float2(launchID.xy) + float2(0.5, 0.5);
   float2 d = 2.0 * (pixelCenter / float2(launchSize.xy)) - 1.0;
 
-  float4 origin = mul(float4(0, 0, 0, 1), pc.cam->viewInverse);
-  float4 target = mul(float4(d, 1, 1), pc.cam->projInverse);
-  float4 direction = mul(float4(normalize(target.xyz), 0), pc.cam->viewInverse);
+  float4 origin    = pc.cam->viewInverse * float4(0, 0, 0, 1);
+  float4 target    = pc.cam->projInverse * float4(d, 1, 1);
+  float4 direction = pc.cam->viewInverse * float4(normalize(target.xyz), 0);
 
   RayDesc ray;
   ray.Origin = origin.xyz;
@@ -65,7 +65,7 @@ void rayGenMain() {
 float2 rotate(float2 v, float angle) {
   float2x2 r = float2x2(cos(angle), -sin(angle),
                         sin(angle),  cos(angle));
-  return mul(v-0.5*DispatchRaysDimensions().xy, r);
+  return r * (v-0.5*DispatchRaysDimensions().xy);
 }
 
 // helper function for GLSL-style mod() that works with negative numbers
@@ -121,8 +121,8 @@ void main() {
   vec2 pixelCenter = gl_LaunchIDEXT.xy + vec2(0.5);
   vec2 d = 2.0 * (pixelCenter / gl_LaunchSizeEXT.xy) - 1.0;
 
-  vec4 origin = cam.viewInverse * vec4(0,0,0,1);
-  vec4 target = cam.projInverse * vec4(d, 1, 1);
+  vec4 origin    = cam.viewInverse * vec4(0,0,0,1);
+  vec4 target    = cam.projInverse * vec4(d, 1, 1);
   vec4 direction = cam.viewInverse * vec4(normalize(target.xyz), 0);
 
   payload = vec3(0.0);

samples/RTX_004_Textures.cpp

@@ -46,9 +46,9 @@ void rayGenMain() {
   float2 pixelCenter = float2(launchID.xy) + float2(0.5, 0.5);
   float2 d = 2.0 * (pixelCenter / float2(launchSize.xy)) - 1.0;
 
-  float4 origin = mul(float4(0, 0, 0, 1), pc.cam->viewInverse);
-  float4 target = mul(float4(d, 1, 1), pc.cam->projInverse);
-  float4 direction = mul(float4(normalize(target.xyz), 0), pc.cam->viewInverse);
+  float4 origin    = pc.cam->viewInverse * float4(0, 0, 0, 1);
+  float4 target    = pc.cam->projInverse * float4(d, 1, 1);
+  float4 direction = pc.cam->viewInverse * float4(normalize(target.xyz), 0);
 
   RayDesc ray;
   ray.Origin = origin.xyz;