vertexShader.txt

#version 440 core

layout(location = 0) in vec3 vertexPosition_modelspace;
layout(location = 1) in vec3 normal;
layout(location = 2) in vec2 textureCoord;

uniform mat4 modelMatrix;
uniform mat4 viewMatrix;
uniform vec3 lamp;

smooth out vec3 fragNormal;
smooth out vec3 fragCoord;
smooth out vec2 texCoord;
out vec3 lampPos;

mat4 mvp;
mat3 normalMat;

void main(void){
    //lightDir = lamp-vertexPosition_modelspace;
    lampPos = lamp;

    vec4 pos;
    pos.xyz = vertexPosition_modelspace;
    pos.w = 1.0;
    mvp = viewMatrix * modelMatrix; //create the model-view-perspective matrix
    gl_Position = pos*mvp; //transform by the MVP
    fragCoord = vec3(pos*mvp);
    texCoord = textureCoord;

    normalMat = mat3(mvp);
    normalMat = inverse(normalMat);
    normalMat = transpose(normalMat);
    fragNormal = normalize(normal * normalMat); //transform the vertex normals with math that i can not comprehend :(
 }