vertexShader

#version 330 core
// Vertex position
layout(location = 0) in vec3 vertexPosition;
layout(location = 1) in vec2 vertexUV;
layout(location = 2) in vec3 vertexNormal;

// The MVP matrix
uniform mat4 Model;
uniform mat4 View;
uniform mat4 Projection;
uniform vec3 LightPosition;

out vec3 normal;
out vec3 toLight;
out vec3 positionWorld;
out vec2 UV;

void main(){
  // Upgrade the vertex position to a mat4 as a static position, and multiply with MVP
  gl_Position = Projection * View * Model * vec4(vertexPosition,1);

  // Vertex in camera space
  vec3 vertexCamera = (View * Model * vec4(vertexPosition,1)).xyz;

  // Vertex to light
  vec3 lightCamera = (View * vec4(LightPosition,1)).xyz;
  toLight = lightCamera - vertexCamera;

  // To cameraspace
  normal = (View * Model * vec4(vertexNormal,0)).xyz; // no scaling allowed in model
  positionWorld = (Model * vec4(vertexPosition,1)).xyz;

  // Passthrough (just lerp)
  UV = vertexUV;
}