#pragma once
#include "gl_batch.h"
#include "../util/matrix.h"

// magic number sue me. yes this float is representable exactly.
const F32 SCREEN_INVALID_POS = -2137000.f;

struct VERTEX3D {
  VEC3 pos;
  VEC2 uv;
  CLR clr;
  U8 sampler;
};

using GL_BATCH3D = GL_BATCH<VERTEX3D>;
struct GL_3D : GL_SHADER_PROGRAM {
  F32 aspect;
  MAT4 projmat;

  VEC2 winsize;
};

// shader init -----------------------------------------------------------
extern GL_3D* gl_3d_init( GL_DATA* gl, VEC2 screensize, const char* shadername );
// sets up projection matrix and sends it to the gpu ------------------------------------------------------------
extern void gl_3d_projection_setup( GL_SHADER_PROGRAM* gl3d, VEC3 pos, F32 fov_deg, F32 yaw, F32 pitch, F32 near, F32 far, VEC2 winsize );
extern void gl_3d_batch_setup( GL_BATCH3D* batch );

// takes a triangle fan not set of triangles
extern void gl_3d_polygon(
  GL_SHADER_PROGRAM* gl3d,
  VERTEX3D* vertices,
  U32 vertices_count,
  GL_TEX2D* tex
);

// calculates triangle set from triangle fan before sending to batch
extern void gl_3d_polygon_fan(
  GL_BATCH3D* batch,
  VERTEX3D* vertices,
  U32 vertices_count,
  GL_TEX2D* tex
);

// draws a set of triangles
extern void gl_3d_polygon(
  GL_BATCH3D* batch,
  VERTEX3D* vertices,
  U32 vertices_count,
  GL_TEX2D* tex
);

extern void gl_3d_plane(
  GL_SHADER_PROGRAM* gl3d,
  VEC3 pos,
  VEC2 size,
  VEC2 rot,
  GL_TEX2D* tex,
  CLR col = CLR::WHITE()
);

extern void gl_3d_plane(
  GL_BATCH3D* batch,
  VEC3 pos,
  VEC2 size,
  VEC2 rot,
  GL_TEX2D* tex,
  CLR col = CLR::WHITE()
);