#version 330 core

// Input vertex attribute (e.g., from your VBO)
// 'layout (location = 0)' matches the first attribute you enable.
layout (location = 0) in vec3 aPos;
layout (location = 1) in vec3 aNormal;

// A "uniform" is a global variable you set from your C++/Java/etc. code.
// This matrix combines your model, view, and projection matrices.
uniform mat4 u_mvp;

flat out vec3 v_Normal;

void main()
{
    // gl_Position is a special built-in variable.
    // It's the final clip-space position of the vertex.
    gl_Position = u_mvp * vec4(aPos, 1.0);

    v_Normal = aNormal;
}