default.vert

#version 330

layout(location = 0) in vec4 position;
uniform vec3 offset;

uniform float near;
uniform float far;
uniform float frustum_scale;

void main() {
    vec4 camera_pos = position + vec4(offset.x, offset.y, offset.z, 0.0);
    vec4 clip_pos;

    clip_pos.xy = camera_pos.xy * frustum_scale;

    clip_pos.z = camera_pos.z * (near + far) / (near - far);
    clip_pos.z += 2 * near * far / (near - far);

    clip_pos.w = -camera_pos.z;

    gl_Position = clip_pos;
}