Bugfix for GLSL: no specular/diffuse + only shadow for lamps

didn't work correct.

source/blender/gpu/intern/gpu_material.c

@@ -682,8 +682,15 @@ static void shade_one_light(GPUShadeInput *shi, GPUShadeResult *shr, GPULamp *la
 			
 			if(lamp->mode & LA_ONLYSHADOW) {
 				GPU_link(mat, "shade_only_shadow", i, shadfac,
-					GPU_dynamic_uniform(&lamp->dynenergy), shi->rgb, shi->specrgb,
-					shr->diff, shr->spec, &shr->diff, &shr->spec);
+					GPU_dynamic_uniform(&lamp->dynenergy), &shadfac);
+				
+				if(!(lamp->mode & LA_NO_DIFF))
+					GPU_link(mat, "shade_only_shadow_diffuse", shadfac, shi->rgb,
+						shr->diff, &shr->diff);
+
+				if(!(lamp->mode & LA_NO_SPEC))
+					GPU_link(mat, "shade_only_shadow_specular", shadfac, shi->specrgb,
+						shr->spec, &shr->spec);
 				
 				add_user_list(&mat->lamps, lamp);
 				add_user_list(&lamp->materials, ma);

source/blender/gpu/intern/gpu_shader_material.glsl

@@ -1483,11 +1483,18 @@ void ramp_rgbtobw(vec3 color, out float outval)
 	outval = color.r*0.3 + color.g*0.58 + color.b*0.12;
 }
 
-void shade_only_shadow(float i, float shadfac, float energy, vec3 rgb, vec3 specrgb, vec4 diff, vec4 spec, out vec4 outdiff, out vec4 outspec)
+void shade_only_shadow(float i, float shadfac, float energy, out float outshadfac)
 {
-	shadfac = i*energy*(1.0 - shadfac);
+	outshadfac = i*energy*(1.0 - shadfac);
+}
 
+void shade_only_shadow_diffuse(float shadfac, vec3 rgb, vec4 diff, out vec4 outdiff)
+{
 	outdiff = diff - vec4(rgb*shadfac, 0.0);
+}
+
+void shade_only_shadow_specular(float shadfac, vec3 specrgb, vec4 spec, out vec4 outspec)
+{
 	outspec = spec - vec4(specrgb*shadfac, 0.0);
 }