/*  RetroArch - A frontend for libretro.
 *  Copyright (C) 2010-2014 - Hans-Kristian Arntzen
 *  Copyright (C) 2011-2014 - Daniel De Matteis
 * 
 *  RetroArch is free software: you can redistribute it and/or modify it under the terms
 *  of the GNU General Public License as published by the Free Software Found-
 *  ation, either version 3 of the License, or (at your option) any later version.
 *
 *  RetroArch is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 *  without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
 *  PURPOSE.  See the GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along with RetroArch.
 *  If not, see <http://www.gnu.org/licenses/>.
 */

#include "gl_common.h"

void gl_load_texture_data(GLuint obj, const struct texture_image *img,
      GLenum wrap, bool linear, bool mipmap)
{
   glBindTexture(GL_TEXTURE_2D, obj);

#ifdef HAVE_PSGL
   mipmap = false;
#endif
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrap);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrap);

   GLint mag_filter = linear ? GL_LINEAR : GL_NEAREST;
   GLint min_filter = linear ? (mipmap ? GL_LINEAR_MIPMAP_LINEAR : GL_LINEAR) :
                               (mipmap ? GL_NEAREST_MIPMAP_NEAREST : GL_NEAREST);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, mag_filter);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, min_filter);

#ifndef HAVE_PSGL
   glPixelStorei(GL_UNPACK_ALIGNMENT, 4);
#endif
   glTexImage2D(GL_TEXTURE_2D,
         0, driver.gfx_use_rgba ? GL_RGBA : RARCH_GL_INTERNAL_FORMAT32,
         img->width, img->height,
         0, driver.gfx_use_rgba ? GL_RGBA : RARCH_GL_TEXTURE_TYPE32,
         RARCH_GL_FORMAT32, img->pixels);
#ifndef HAVE_PSGL
   if (mipmap)
      glGenerateMipmap(GL_TEXTURE_2D);
#endif
}

bool gl_load_luts(const struct gfx_shader *generic_shader,
      GLuint *lut_textures)
{
   unsigned i;
   unsigned num_luts = min(generic_shader->luts, GFX_MAX_TEXTURES);

   if (!generic_shader->luts)
      return true;

   /*  Original shader_glsl.c code only generated one 
    *  texture handle.  I assume it was a bug, but if not, 
    *  replace num_luts with 1 when GLSL is used. */
   glGenTextures(num_luts, lut_textures);
   for (i = 0; i < num_luts; i++)
   {
      struct texture_image img = {0};
      RARCH_LOG("Loading texture image from: \"%s\" ...\n",
            generic_shader->lut[i].path);

      if (!texture_image_load(&img, generic_shader->lut[i].path))
      {
         RARCH_ERR("Failed to load texture image from: \"%s\"\n",
               generic_shader->lut[i].path);
         return false;
      }

      gl_load_texture_data(lut_textures[i], &img,
            driver.video->wrap_type_to_enum(generic_shader->lut[i].wrap),
            generic_shader->lut[i].filter != RARCH_FILTER_NEAREST,
            generic_shader->lut[i].mipmap);
      texture_image_free(&img);
   }

   glBindTexture(GL_TEXTURE_2D, 0);
   return true;
}

void gl_shader_set_coords(gl_t *gl,
      const struct gl_coords *coords, const math_matrix *mat)
{
   if (!gl->shader->set_coords(coords)) 
   {
#ifndef NO_GL_FF_VERTEX
      /* Fall back to FF-style if needed and possible. */
      glClientActiveTexture(GL_TEXTURE1);
      glTexCoordPointer(2, GL_FLOAT, 0, coords->lut_tex_coord);
      glEnableClientState(GL_TEXTURE_COORD_ARRAY);

      glClientActiveTexture(GL_TEXTURE0);
      glVertexPointer(2, GL_FLOAT, 0, coords->vertex);
      glEnableClientState(GL_VERTEX_ARRAY);

      glColorPointer(4, GL_FLOAT, 0, coords->color);
      glEnableClientState(GL_COLOR_ARRAY);

      glTexCoordPointer(2, GL_FLOAT, 0, coords->tex_coord);
      glEnableClientState(GL_TEXTURE_COORD_ARRAY);
#endif
   }
   if (!gl->shader->set_mvp(gl, mat))
   {
#ifndef NO_GL_FF_MATRIX
      /* Fall back to FF-style if needed and possible. */
      glMatrixMode(GL_PROJECTION);
      glLoadMatrixf(mat->data);
      glMatrixMode(GL_MODELVIEW);
      glLoadIdentity();
#endif
   }
}