Fix minor difference between ubershader and specialized vshaders

GPU/Common/ShaderUniforms.cpp

@@ -283,6 +283,7 @@ void BaseUpdateUniforms(UB_VS_FS_Base *ub, uint64_t dirtyUniforms, bool flipView
 }
 
 // For "light ubershader" bits.
+// TODO: We pack these bits even when not using ubershader lighting. Maybe not bother.
 uint32_t PackLightControlBits() {
  // Bit organization
  // Bottom 4 bits are enable bits for each light.

GPU/Common/VertexShaderGenerator.cpp

@@ -1012,6 +1012,7 @@ bool GenerateVertexShader(const VShaderID &id, char *buffer, const ShaderLanguag
  }
  }
 
+ // NOTE: Can't change this without updaing uniform buffer declarations (for D3D11 and VK, the one in ShaderUniforms.h).
  bool useIndexing = compat.shaderLanguage == HLSL_D3D11 || compat.shaderLanguage == GLSL_VULKAN;
 
  char iStr[4];
@@ -1062,7 +1063,7 @@ bool GenerateVertexShader(const VShaderID &id, char *buffer, const ShaderLanguag
  p.C(" ldot = u_matspecular.a > 0.0 ? pow(max(ldot, 0.0), u_matspecular.a) : 1.0;\n");
  p.C(" }\n");
  p.F(" diffuse = (u_lightdiffuse%s * diffuseColor) * max(ldot, 0.0);\n", iStr);
- p.C(" if (comp == 0x1u && ldot > 0.0) {\n"); // do specular
+ p.C(" if (comp == 0x1u && ldot >= 0.0) {\n"); // do specular. note - must allow for the >= case, since the u_matspecular.a <= 0.0 case relies on it.
  p.C(" if (u_matspecular.a > 0.0) {\n");
  p.C(" ldot = dot(normalize(toLight + vec3(0.0, 0.0, 1.0)), worldnormal);\n");
  p.C(" ldot = pow(max(ldot, 0.0), u_matspecular.a);\n");