GPU: Correct shade mapping with 0,0,0 light pos.

May need to audit more normalize() usage, if it's consistent in other places.
hrydgard · Nov 18, 2018 · 0c5c776 · 0c5c776
1 parent 986371c
commit 0c5c776
Show file tree

Hide file tree

Showing 4 changed files with 26 additions and 6 deletions.
diff --git a/GPU/Common/SoftwareTransformCommon.cpp b/GPU/Common/SoftwareTransformCommon.cpp
@@ -397,9 +397,17 @@ void SoftwareTransform(
 					auto getLPos = [&](int l) {
 						return Vec3f(getLPosFloat(l, 0), getLPosFloat(l, 1), getLPosFloat(l, 2));
 					};
+					auto calcShadingLPos = [&](int l) {
+						Vec3f pos = getLPos(l);
+						if (pos.Length() == 0.0f) {
+							return Vec3f(0.0f, 0.0f, 1.0f);
+						} else {
+							return pos.Normalized();
+						}
+					};
 					// Might not have lighting enabled, so don't use lighter.
-					Vec3f lightpos0 = getLPos(gstate.getUVLS0()).Normalized();
-					Vec3f lightpos1 = getLPos(gstate.getUVLS1()).Normalized();
+					Vec3f lightpos0 = calcShadingLPos(gstate.getUVLS0());
+					Vec3f lightpos1 = calcShadingLPos(gstate.getUVLS1());
 
 					uv[0] = (1.0f + Dot(lightpos0, worldnormal))/2.0f;
 					uv[1] = (1.0f + Dot(lightpos1, worldnormal))/2.0f;

diff --git a/GPU/Directx9/VertexShaderGeneratorDX9.cpp b/GPU/Directx9/VertexShaderGeneratorDX9.cpp
@@ -715,7 +715,11 @@ void GenerateVertexShaderHLSL(const VShaderID &id, char *buffer, ShaderLanguage
 				break;
 
 			case GE_TEXMAP_ENVIRONMENT_MAP:  // Shade mapping - use dots from light sources.
-				WRITE(p, "  Out.v_texcoord = float3(u_uvscaleoffset.xy * float2(1.0 + dot(normalize(u_lightpos%i), worldnormal), 1.0 + dot(normalize(u_lightpos%i), worldnormal)) * 0.5, 1.0);\n", ls0, ls1);
+				{
+					std::string lightFactor0 = StringFromFormat("(length(u_lightpos%i) == 0.0 ? worldnormal.z : dot(normalize(u_lightpos%i), worldnormal))", ls0, ls0);
+					std::string lightFactor1 = StringFromFormat("(length(u_lightpos%i) == 0.0 ? worldnormal.z : dot(normalize(u_lightpos%i), worldnormal))", ls1, ls1);
+					WRITE(p, "  Out.v_texcoord = float3(u_uvscaleoffset.xy * float2(1.0 + %s, 1.0 + %s) * 0.5, 1.0);\n", lightFactor0.c_str(), lightFactor1.c_str());
+				}
 				break;
 
 			default:

diff --git a/GPU/GLES/VertexShaderGeneratorGLES.cpp b/GPU/GLES/VertexShaderGeneratorGLES.cpp
@@ -810,7 +810,11 @@ void GenerateVertexShader(const VShaderID &id, char *buffer, uint32_t *attrMask,
 				break;
 
 			case GE_TEXMAP_ENVIRONMENT_MAP:  // Shade mapping - use dots from light sources.
-				WRITE(p, "  v_texcoord = vec3(u_uvscaleoffset.xy * vec2(1.0 + dot(normalize(u_lightpos%i), worldnormal), 1.0 + dot(normalize(u_lightpos%i), worldnormal)) * 0.5, 1.0);\n", ls0, ls1);
+				{
+					std::string lightFactor0 = StringFromFormat("(length(u_lightpos%i) == 0.0 ? worldnormal.z : dot(normalize(u_lightpos%i), worldnormal))", ls0, ls0);
+					std::string lightFactor1 = StringFromFormat("(length(u_lightpos%i) == 0.0 ? worldnormal.z : dot(normalize(u_lightpos%i), worldnormal))", ls1, ls1);
+					WRITE(p, "  v_texcoord = vec3(u_uvscaleoffset.xy * vec2(1.0 + %s, 1.0 + %s) * 0.5, 1.0);\n", lightFactor0.c_str(), lightFactor1.c_str());
+				}
 				break;
 
 			default:

diff --git a/GPU/Vulkan/VertexShaderGeneratorVulkan.cpp b/GPU/Vulkan/VertexShaderGeneratorVulkan.cpp
@@ -602,8 +602,12 @@ bool GenerateVulkanGLSLVertexShader(const VShaderID &id, char *buffer) {
 			break;
 
 			case GE_TEXMAP_ENVIRONMENT_MAP:  // Shade mapping - use dots from light sources.
-				WRITE(p, "  v_texcoord = vec3(base.uvscaleoffset.xy * vec2(1.0 + dot(normalize(light.pos[%i]), worldnormal), 1.0 + dot(normalize(light.pos[%i]), worldnormal)) * 0.5, 1.0);\n", ls0, ls1);
-				break;
+			{
+				std::string lightFactor0 = StringFromFormat("(length(light.pos[%i]) == 0.0 ? worldnormal.z : dot(normalize(light.pos[%i]), worldnormal))", ls0, ls0);
+				std::string lightFactor1 = StringFromFormat("(length(light.pos[%i]) == 0.0 ? worldnormal.z : dot(normalize(light.pos[%i]), worldnormal))", ls1, ls1);
+				WRITE(p, "  v_texcoord = vec3(base.uvscaleoffset.xy * vec2(1.0 + %s, 1.0 + %s) * 0.5, 1.0);\n", lightFactor0.c_str(), lightFactor1.c_str());
+			}
+			break;
 
 			default:
 				// ILLEGAL