Merge pull request #12924 from vnen/light-shader

Enable light shaders when light variables are used

drivers/gles3/shader_compiler_gles3.cpp

@@ -741,6 +741,7 @@ ShaderCompilerGLES3::ShaderCompilerGLES3() {
 	actions[VS::SHADER_CANVAS_ITEM].usage_defines["NORMAL"] = "#define NORMAL_USED\n";
 	actions[VS::SHADER_CANVAS_ITEM].usage_defines["NORMALMAP"] = "#define NORMALMAP_USED\n";
 	actions[VS::SHADER_CANVAS_ITEM].usage_defines["SHADOW_COLOR"] = "#define SHADOW_COLOR_USED\n";
+	actions[VS::SHADER_CANVAS_ITEM].usage_defines["LIGHT"] = "#define USE_LIGHT_SHADER_CODE\n";
 
 	actions[VS::SHADER_CANVAS_ITEM].render_mode_defines["skip_vertex_transform"] = "#define SKIP_TRANSFORM_USED\n";
 
@@ -828,6 +829,9 @@ ShaderCompilerGLES3::ShaderCompilerGLES3() {
 	actions[VS::SHADER_SPATIAL].usage_defines["SCREEN_TEXTURE"] = "#define SCREEN_TEXTURE_USED\n";
 	actions[VS::SHADER_SPATIAL].usage_defines["SCREEN_UV"] = "#define SCREEN_UV_USED\n";
 
+	actions[VS::SHADER_SPATIAL].usage_defines["DIFFUSE_LIGHT"] = "#define USE_LIGHT_SHADER_CODE\n";
+	actions[VS::SHADER_SPATIAL].usage_defines["SPECULAR_LIGHT"] = "#define USE_LIGHT_SHADER_CODE\n";
+
 	actions[VS::SHADER_SPATIAL].renames["SSS_STRENGTH"] = "sss_strength";
 
 	actions[VS::SHADER_SPATIAL].render_mode_defines["skip_vertex_transform"] = "#define SKIP_TRANSFORM_USED\n";