Improve material loading and add coordinate system model

shaders/mesh-fragment.glsl

@@ -9,6 +9,14 @@ struct Material {
 	sampler2D specular1;
 	sampler2D specular2;
 	sampler2D specular3;
+	sampler2D ambient0;
+	sampler2D ambient1;
+	bool use_diff_color;
+	vec3 diff_color;
+	bool use_spec_color;
+	vec3 spec_color;
+	int use_amb_color;
+	vec3 amb_color;
 };
 
 out vec4 fragmentColor;
@@ -26,8 +34,28 @@ void main()
 	const float light_spec = 0.4;
 	const float light_diff = 0.7;
 
-	vec3 diffuseTexCol = vec3(texture(material.diffuse0, TexCoord));
-	vec3 specularTexCol = vec3(texture(material.specular0, TexCoord));
+	vec3 diffuseTexCol;
+	if (material.use_diff_color) {
+		diffuseTexCol = material.diff_color;
+	} else {
+		diffuseTexCol = vec3(texture(material.diffuse0, TexCoord));
+	}
+
+	vec3 specularTexCol;
+	if (material.use_spec_color) {
+		specularTexCol = material.spec_color;
+	} else {
+		specularTexCol = vec3(texture(material.specular0, TexCoord));
+	}
+
+	vec3 ambTexCol;
+	if (material.use_amb_color == 0) {
+		ambTexCol = vec3(texture(material.ambient0, TexCoord));
+	} else if (material.use_amb_color == 1) {
+		ambTexCol = diffuseTexCol * 0.5;
+	} else if (material.use_amb_color == 2) {
+		ambTexCol = material.amb_color;
+	}
 
 	vec3 normal_n = normalize(Normal);
 	vec3 light_dir_n = normalize(light_direction);