Phong shader problem

[neuralsandwich]

Issue with line 20 (commit 5676c216c1f6f3d9da8042d0517cc4b9d6e5d4b4) of phong.vert, which stops the shader from linking.

The overall lighting effect doesn't seem like it is correct either.

This doesn't work

void main()
{
  // Past through position
  vertex_position = (model * position).xyz;

  // Transform position
  gl_Position = MVP * vec4(position, 1.0);

  // Updating normal with normal matrix
  transformed_normal = normal_matrix * normal;

  // Output tex coord
  vertex_tex_coord = tex_coord;

}

This works

void main()
{
  // Past through position
  //vertex_position = (model * position).xyz;

  // Transform position
  gl_Position = MVP * vec4(position, 1.0);

  // Updating normal with normal matrix
  transformed_normal = normal_matrix * normal;

  // Output tex coord
  vertex_tex_coord = tex_coord;

}

[7thsanctum]

You can't multiply a mat4 by a vec3. To get around this you could multiply it by a vec4 instead. do something like

vertex_position = (model * vec4(position,1)).xyz;

[neuralsandwich]

I was thinking that in the workbook by Kevin Chalmers it said to do it. I am still getting used to GLM and OpenGL so I wasn't sure.

I'll try it and see what happens!