PHONG minus report

gloom-rs/shaders/simple.frag

@@ -2,11 +2,34 @@
 
 in vec4 fragment_colors;
 in vec3 normal_vec;
+in vec3 viewing_vec;
 out vec4 color;
 
 void main()
 {
-    float lightVec = normal_vec.x * -0.8 + normal_vec.y * 0.5 + normal_vec.z * -0.6;
-    vec3 albedo = vec3(fragment_colors) * max(0, lightVec);
+    // Constants
+    vec3 i_ambient = vec3(0.4);
+    vec3 i_diffuse = vec3(0.6);
+    vec3 i_spec = vec3(0.8);
+
+    float k_ambient = 0.5;
+    float k_diffuse = 0.9;
+    float k_spec = 0.6;
+    float alpha = 8;
+
+    // Light vector
+    vec3 L = normalize(vec3(-0.8, 0.5, -0.6));
+
+    // Reflected light vector
+    vec3 R = 2 * dot(normalize(normal_vec), L) * normalize(normal_vec) - L;
+
+    // Component vectors
+    vec3 ambient = k_ambient * i_ambient;
+    vec3 diff = k_diffuse * max(dot(normalize(normal_vec), L), 0.0) * i_diffuse;
+    vec3 spec = k_spec * pow(max(dot(R, normalize(viewing_vec)), 0.0), alpha) * i_spec;
+
+    // Final color vector
+    vec3 intensity = ambient + diff + spec;
+    vec3 albedo = fragment_colors.rgb * intensity;
     color = vec4(albedo, 1);
 }

gloom-rs/shaders/simple.vert

@@ -7,11 +7,12 @@ uniform mat4 mvp_transform;
 uniform mat4 model_transform;
 out vec4 fragment_colors;
 out vec3 normal_vec;
-
+out vec3 viewing_vec;
 
 void main()
 {
     gl_Position = mvp_transform * vec4(position, 1.0f);
     fragment_colors = vertex_colors;
     normal_vec = normalize(mat3(model_transform) * normal);
+    viewing_vec = vec3(-gl_Position);
 }