I’m playing around with opengl and shading. Doing so I achieve some transparency effect which I cannot explain (see image).

I suspected normals at first, checked them in blender, event regenerated them, tried out everything in webgl using three.js and it looks all fine - as it should. So I believe what that tells me is that the problem is not related to normals.

Now using it in my opengl program with SDL and assimp to load the model I see through the teapot, bits that should be obscurred. I have depth test enabled also and played around with the shaders but to no avail.

My shaders are the kind that should do the job for ambient and diffuse light with a light source.

The teapot is just given any color and I don’t set the alpha channel to use transparency…

```
#version 300 es
in vec3 position;
in vec3 normal;
uniform mat4 model;
uniform mat4 view;
uniform mat4 projection;
out vec3 norm;
out vec3 pos;
void main() {
pos = vec3(model * vec4(position, 1.0)).xyz;
gl_Position = projection * view * vec4(pos, 1.0);
norm = normalize(mat3(transpose(inverse(model))) * normal);
}
```

and the fragment shader:

```
#version 300 es
#ifdef GL_ES
precision highp float;
#endif
in vec3 norm;
in vec3 pos;
uniform vec3 ambientLight;
uniform vec3 objectColor;
uniform vec3 sunDirection;
uniform vec3 sunLightColor;
out vec4 fragColor;
void main() {
vec3 lightDir = normalize(sunDirection - pos);
float diff = max(dot(norm, lightDir), 0.0);
vec3 diffuse = diff * sunLightColor;
fragColor = normalize(vec4((ambientLight + diffuse) * objectColor, 1.0));
}
```

Any ideas from people who have experience with these sort of effects will be appreciated.