src/video/gl/gl_renderer.cpp

   1 //  SuperTux
   2 //  Copyright (C) 2006 Matthias Braun <matze@braunis.de>
   3 //      Updated by GiBy 2013 for SDL2 <giby_the_kid@yahoo.fr>
   4 //
   5 //  This program is free software: you can redistribute it and/or modify
   6 //  it under the terms of the GNU General Public License as published by
   7 //  the Free Software Foundation, either version 3 of the License, or
   8 //  (at your option) any later version.
   9 //
  10 //  This program is distributed in the hope that it will be useful,
  11 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 //  GNU General Public License for more details.
  14 //
  15 //  You should have received a copy of the GNU General Public License
  16 //  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17
  18 #include "video/gl/gl_renderer.hpp"
  19
  20 #include <iomanip>
  21 #include <iostream>
  22 #include <physfs.h>
  23 #include "SDL.h"
  24 //#include "SDL/SDL.h"
  25 //#include "SDL/SDL_opengl.h"
  26
  27 #include "supertux/gameconfig.hpp"
  28 #include "supertux/globals.hpp"
  29 #include "video/drawing_request.hpp"
  30 #include "video/gl/gl_surface_data.hpp"
  31 #include "video/gl/gl_texture.hpp"
  32 #define LIGHTMAP_DIV 5
  33
  34 #ifdef GL_VERSION_ES_CM_1_0
  35 #  define glOrtho glOrthof
  36 #endif
  37
  38 GLRenderer::GLRenderer() :
  39   desktop_size(-1, -1),
  40   screen_size(-1, -1),
  41   fullscreen_active(false),
  42   last_texture(static_cast<GLuint> (-1))
  43 {
  44   Renderer::instance_ = this;
  45
  46 #if SDL_MAJOR_VERSION > 1 || SDL_MINOR_VERSION > 2 || (SDL_MINOR_VERSION == 2 && SDL_PATCHLEVEL >= 10)
  47   // unfortunately only newer SDLs have these infos.
  48   // This must be called before SDL_SetVideoMode() or it will return
  49   // the window size instead of the desktop size.
  50 #ifdef OLD_SDL1
  51   const SDL_VideoInfo *info = SDL_GetVideoInfo();
  52   if (info)
  53   {
  54       desktop_size = Size(info->current_w, info->current_h);
  55   }
  56 #else
  57   desktop_size = Size(1920, 1080);
  58 #endif
  59 #endif
  60
  61   if(texture_manager != 0)
  62     texture_manager->save_textures();
  63
  64 #ifdef SDL_GL_SWAP_CONTROL
  65   if(config->try_vsync) {
  66     /* we want vsync for smooth scrolling */
  67      SDL_GL_SetSwapInterval(1);
  68   }
  69 #endif
  70
  71 #ifdef OLD_SDL1
  72   SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
  73
  74    // FIXME: Hu? 16bit rendering?
  75    SDL_GL_SetAttribute(SDL_GL_RED_SIZE,   5);
  76    SDL_GL_SetAttribute(SDL_GL_GREEN_SIZE, 5);
  77    SDL_GL_SetAttribute(SDL_GL_BLUE_SIZE,  5);
  78 #endif
  79
  80   if(g_config->use_fullscreen)
  81   {
  82     apply_video_mode(g_config->fullscreen_size, true);
  83   }
  84   else
  85   {
  86     apply_video_mode(g_config->window_size, false);
  87   }
  88
  89   // setup opengl state and transform
  90   glDisable(GL_DEPTH_TEST);
  91   glDisable(GL_CULL_FACE);
  92   glEnable(GL_TEXTURE_2D);
  93   glEnable(GL_BLEND);
  94   glEnableClientState(GL_VERTEX_ARRAY);
  95   glEnableClientState(GL_TEXTURE_COORD_ARRAY);
  96   glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
  97
  98   // Init the projection matrix, viewport and stuff
  99   apply_config();
 100
 101   if(texture_manager == 0)
 102     texture_manager = new TextureManager();
 103   else
 104     texture_manager->reload_textures();
 105
 106 #ifndef GL_VERSION_ES_CM_1_0
 107   GLenum err = glewInit();
 108   if (GLEW_OK != err)
 109   {
 110     std::ostringstream out;
 111     out << "GLRenderer: " << glewGetErrorString(err);
 112     throw std::runtime_error(out.str());
 113   }
 114   log_info << "Using GLEW " << glewGetString(GLEW_VERSION) << std::endl;
 115   log_info << "GLEW_ARB_texture_non_power_of_two: " << static_cast<int>(GLEW_ARB_texture_non_power_of_two) << std::endl;
 116 #endif
 117 }
 118
 119 GLRenderer::~GLRenderer()
 120 {
 121   SDL_GL_DeleteContext(glcontext);
 122   SDL_DestroyWindow(window);
 123 }
 124
 125 void
 126 GLRenderer::draw_surface(const DrawingRequest& request)
 127 {
 128   const Surface* surface = (const Surface*) request.request_data;
 129   if(surface == NULL)
 130   {
 131     return;
 132   }
 133   GLTexture* gltexture = static_cast<GLTexture*>(surface->get_texture().get());
 134   if(gltexture == NULL)
 135   {
 136     return;
 137   }
 138   GLSurfaceData *surface_data = static_cast<GLSurfaceData*>(surface->get_surface_data());
 139   if(surface_data == NULL)
 140   {
 141     return;
 142   }
 143
 144   GLuint th = gltexture->get_handle();
 145   if (th != last_texture) {
 146     last_texture = th;
 147     glBindTexture(GL_TEXTURE_2D, th);
 148   }
 149   intern_draw(request.pos.x, request.pos.y,
 150               request.pos.x + surface->get_width(),
 151               request.pos.y + surface->get_height(),
 152               surface_data->get_uv_left(),
 153               surface_data->get_uv_top(),
 154               surface_data->get_uv_right(),
 155               surface_data->get_uv_bottom(),
 156               request.angle,
 157               request.alpha,
 158               request.color,
 159               request.blend,
 160               request.drawing_effect);
 161 }
 162
 163 void
 164 GLRenderer::draw_surface_part(const DrawingRequest& request)
 165 {
 166   const SurfacePartRequest* surfacepartrequest
 167     = (SurfacePartRequest*) request.request_data;
 168   const Surface* surface = surfacepartrequest->surface;
 169   boost::shared_ptr<GLTexture> gltexture = boost::dynamic_pointer_cast<GLTexture>(surface->get_texture());
 170   GLSurfaceData *surface_data = reinterpret_cast<GLSurfaceData *>(surface->get_surface_data());
 171
 172   float uv_width = surface_data->get_uv_right() - surface_data->get_uv_left();
 173   float uv_height = surface_data->get_uv_bottom() - surface_data->get_uv_top();
 174
 175   float uv_left = surface_data->get_uv_left() + (uv_width * surfacepartrequest->source.x) / surface->get_width();
 176   float uv_top = surface_data->get_uv_top() + (uv_height * surfacepartrequest->source.y) / surface->get_height();
 177   float uv_right = surface_data->get_uv_left() + (uv_width * (surfacepartrequest->source.x + surfacepartrequest->size.x)) / surface->get_width();
 178   float uv_bottom = surface_data->get_uv_top() + (uv_height * (surfacepartrequest->source.y + surfacepartrequest->size.y)) / surface->get_height();
 179
 180   GLuint th = gltexture->get_handle();
 181   if (th != last_texture) {
 182     last_texture = th;
 183     glBindTexture(GL_TEXTURE_2D, th);
 184   }
 185   intern_draw(request.pos.x, request.pos.y,
 186               request.pos.x + surfacepartrequest->size.x,
 187               request.pos.y + surfacepartrequest->size.y,
 188               uv_left,
 189               uv_top,
 190               uv_right,
 191               uv_bottom,
 192               0.0,
 193               request.alpha,
 194               request.color,
 195               Blend(),
 196               request.drawing_effect);
 197 }
 198
 199 void
 200 GLRenderer::draw_gradient(const DrawingRequest& request)
 201 {
 202   const GradientRequest* gradientrequest
 203     = (GradientRequest*) request.request_data;
 204   const Color& top = gradientrequest->top;
 205   const Color& bottom = gradientrequest->bottom;
 206
 207   glDisable(GL_TEXTURE_2D);
 208   glDisableClientState(GL_TEXTURE_COORD_ARRAY);
 209   glEnableClientState(GL_COLOR_ARRAY);
 210
 211   float vertices[] = {
 212     0, 0,
 213     float(SCREEN_WIDTH), 0,
 214     float(SCREEN_WIDTH), float(SCREEN_HEIGHT),
 215     0, float(SCREEN_HEIGHT)
 216   };
 217   glVertexPointer(2, GL_FLOAT, 0, vertices);
 218
 219   float colors[] = {
 220     top.red, top.green, top.blue, top.alpha,
 221     top.red, top.green, top.blue, top.alpha,
 222     bottom.red, bottom.green, bottom.blue, bottom.alpha,
 223     bottom.red, bottom.green, bottom.blue, bottom.alpha,
 224   };
 225   glColorPointer(4, GL_FLOAT, 0, colors);
 226
 227   glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
 228
 229   glDisableClientState(GL_COLOR_ARRAY);
 230   glEnableClientState(GL_TEXTURE_COORD_ARRAY);
 231
 232   glEnable(GL_TEXTURE_2D);
 233   glColor4f(1, 1, 1, 1);
 234 }
 235
 236 void
 237 GLRenderer::draw_filled_rect(const DrawingRequest& request)
 238 {
 239   const FillRectRequest* fillrectrequest
 240     = (FillRectRequest*) request.request_data;
 241
 242   glDisable(GL_TEXTURE_2D);
 243   glColor4f(fillrectrequest->color.red, fillrectrequest->color.green,
 244             fillrectrequest->color.blue, fillrectrequest->color.alpha);
 245   glDisableClientState(GL_TEXTURE_COORD_ARRAY);
 246
 247   if (fillrectrequest->radius != 0.0f)
 248   {
 249     // draw round rect
 250     // Keep radius in the limits, so that we get a circle instead of
 251     // just graphic junk
 252     float radius = std::min(fillrectrequest->radius,
 253                             std::min(fillrectrequest->size.x/2,
 254                                      fillrectrequest->size.y/2));
 255
 256     // inner rectangle
 257     Rectf irect(request.pos.x    + radius,
 258                request.pos.y    + radius,
 259                request.pos.x + fillrectrequest->size.x - radius,
 260                request.pos.y + fillrectrequest->size.y - radius);
 261
 262     int n = 8;
 263     int p = 0;
 264     std::vector<float> vertices((n+1) * 4 * 2);
 265
 266     for(int i = 0; i <= n; ++i)
 267     {
 268       float x = sinf(i * (M_PI/2) / n) * radius;
 269       float y = cosf(i * (M_PI/2) / n) * radius;
 270
 271       vertices[p++] = irect.get_left() - x;
 272       vertices[p++] = irect.get_top()  - y;
 273
 274       vertices[p++] = irect.get_right() + x;
 275       vertices[p++] = irect.get_top()   - y;
 276     }
 277
 278     for(int i = 0; i <= n; ++i)
 279     {
 280       float x = cosf(i * (M_PI/2) / n) * radius;
 281       float y = sinf(i * (M_PI/2) / n) * radius;
 282
 283       vertices[p++] = irect.get_left()   - x;
 284       vertices[p++] = irect.get_bottom() + y;
 285
 286       vertices[p++] = irect.get_right()  + x;
 287       vertices[p++] = irect.get_bottom() + y;
 288     }
 289
 290     glVertexPointer(2, GL_FLOAT, 0, &*vertices.begin());
 291     glDrawArrays(GL_TRIANGLE_STRIP, 0,  vertices.size()/2);
 292   }
 293   else
 294   {
 295     float x = request.pos.x;
 296     float y = request.pos.y;
 297     float w = fillrectrequest->size.x;
 298     float h = fillrectrequest->size.y;
 299
 300     float vertices[] = {
 301       x,   y,
 302       x+w, y,
 303       x+w, y+h,
 304       x,   y+h
 305     };
 306     glVertexPointer(2, GL_FLOAT, 0, vertices);
 307
 308     glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
 309   }
 310
 311   glEnableClientState(GL_TEXTURE_COORD_ARRAY);
 312   glEnable(GL_TEXTURE_2D);
 313   glColor4f(1, 1, 1, 1);
 314 }
 315
 316 void
 317 GLRenderer::draw_inverse_ellipse(const DrawingRequest& request)
 318 {
 319   const InverseEllipseRequest* ellipse = (InverseEllipseRequest*)request.request_data;
 320
 321   glDisable(GL_TEXTURE_2D);
 322   glColor4f(ellipse->color.red,  ellipse->color.green,
 323             ellipse->color.blue, ellipse->color.alpha);
 324
 325   float x = request.pos.x;
 326   float y = request.pos.y;
 327   float w = ellipse->size.x/2.0f;
 328   float h = ellipse->size.y/2.0f;
 329
 330   static const int slices = 16;
 331   static const int points = (slices+1) * 12;
 332
 333   float vertices[points * 2];
 334   int   p = 0;
 335
 336   // Bottom
 337   vertices[p++] = SCREEN_WIDTH; vertices[p++] = SCREEN_HEIGHT;
 338   vertices[p++] = 0;            vertices[p++] = SCREEN_HEIGHT;
 339   vertices[p++] = x;            vertices[p++] = y+h;
 340
 341   // Top
 342   vertices[p++] = SCREEN_WIDTH; vertices[p++] = 0;
 343   vertices[p++] = 0;            vertices[p++] = 0;
 344   vertices[p++] = x;            vertices[p++] = y-h;
 345
 346   // Left
 347   vertices[p++] = SCREEN_WIDTH; vertices[p++] = 0;
 348   vertices[p++] = SCREEN_WIDTH; vertices[p++] = SCREEN_HEIGHT;
 349   vertices[p++] = x+w;          vertices[p++] = y;
 350
 351   // Right
 352   vertices[p++] = 0;            vertices[p++] = 0;
 353   vertices[p++] = 0;            vertices[p++] = SCREEN_HEIGHT;
 354   vertices[p++] = x-w;          vertices[p++] = y;
 355
 356   for(int i = 0; i < slices; ++i)
 357   {
 358     float ex1 = sinf(M_PI/2 / slices * i) * w;
 359     float ey1 = cosf(M_PI/2 / slices * i) * h;
 360
 361     float ex2 = sinf(M_PI/2 / slices * (i+1)) * w;
 362     float ey2 = cosf(M_PI/2 / slices * (i+1)) * h;
 363
 364     // Bottom/Right
 365     vertices[p++] = SCREEN_WIDTH; vertices[p++] = SCREEN_HEIGHT;
 366     vertices[p++] = x + ex1;      vertices[p++] = y + ey1;
 367     vertices[p++] = x + ex2;      vertices[p++] = y + ey2;
 368
 369     // Top/Left
 370     vertices[p++] = 0;            vertices[p++] = 0;
 371     vertices[p++] = x - ex1;      vertices[p++] = y - ey1;
 372     vertices[p++] = x - ex2;      vertices[p++] = y - ey2;
 373
 374     // Top/Right
 375     vertices[p++] = SCREEN_WIDTH; vertices[p++] = 0;
 376     vertices[p++] = x + ex1;      vertices[p++] = y - ey1;
 377     vertices[p++] = x + ex2;      vertices[p++] = y - ey2;
 378
 379     // Bottom/Left
 380     vertices[p++] = 0;            vertices[p++] = SCREEN_HEIGHT;
 381     vertices[p++] = x - ex1;      vertices[p++] = y + ey1;
 382     vertices[p++] = x - ex2;      vertices[p++] = y + ey2;
 383   }
 384
 385   glDisableClientState(GL_TEXTURE_COORD_ARRAY);
 386   glVertexPointer(2, GL_FLOAT, 0, vertices);
 387
 388   glDrawArrays(GL_TRIANGLES, 0, points);
 389
 390   glEnableClientState(GL_TEXTURE_COORD_ARRAY);
 391
 392   glEnable(GL_TEXTURE_2D);
 393   glColor4f(1, 1, 1, 1);
 394 }
 395
 396 void
 397 GLRenderer::do_take_screenshot()
 398 {
 399   // [Christoph] TODO: Yes, this method also takes care of the actual disk I/O. Split it?
 400
 401   SDL_Surface *shot_surf;
 402   // create surface to hold screenshot
 403 #if SDL_BYTEORDER == SDL_BIG_ENDIAN
 404   shot_surf = SDL_CreateRGBSurface(SDL_SWSURFACE, SCREEN_WIDTH, SCREEN_HEIGHT, 24, 0x00FF0000, 0x0000FF00, 0x000000FF, 0);
 405 #else
 406   shot_surf = SDL_CreateRGBSurface(SDL_SWSURFACE, SCREEN_WIDTH, SCREEN_HEIGHT, 24, 0x000000FF, 0x0000FF00, 0x00FF0000, 0);
 407 #endif
 408   if (!shot_surf) {
 409     log_warning << "Could not create RGB Surface to contain screenshot" << std::endl;
 410     return;
 411   }
 412
 413   // read pixels into array
 414   char* pixels = new char[3 * SCREEN_WIDTH * SCREEN_HEIGHT];
 415   if (!pixels) {
 416     log_warning << "Could not allocate memory to store screenshot" << std::endl;
 417     SDL_FreeSurface(shot_surf);
 418     return;
 419   }
 420   glPixelStorei(GL_PACK_ALIGNMENT, 1);
 421   glReadPixels(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT, GL_RGB, GL_UNSIGNED_BYTE, pixels);
 422
 423   // copy array line-by-line
 424   for (int i = 0; i < SCREEN_HEIGHT; i++) {
 425     char* src = pixels + (3 * SCREEN_WIDTH * (SCREEN_HEIGHT - i - 1));
 426     if(SDL_MUSTLOCK(shot_surf))
 427     {
 428       SDL_LockSurface(shot_surf);
 429     }
 430     char* dst = ((char*)shot_surf->pixels) + i * shot_surf->pitch;
 431     memcpy(dst, src, 3 * SCREEN_WIDTH);
 432     if(SDL_MUSTLOCK(shot_surf))
 433     {
 434       SDL_UnlockSurface(shot_surf);
 435     }
 436   }
 437
 438   // free array
 439   delete[](pixels);
 440
 441   // save screenshot
 442   static const std::string writeDir = PHYSFS_getWriteDir();
 443   static const std::string dirSep = PHYSFS_getDirSeparator();
 444   static const std::string baseName = "screenshot";
 445   static const std::string fileExt = ".bmp";
 446   std::string fullFilename;
 447   for (int num = 0; num < 1000; num++) {
 448     std::ostringstream oss;
 449     oss << baseName;
 450     oss << std::setw(3) << std::setfill('0') << num;
 451     oss << fileExt;
 452     std::string fileName = oss.str();
 453     fullFilename = writeDir + dirSep + fileName;
 454     if (!PHYSFS_exists(fileName.c_str())) {
 455       SDL_SaveBMP(shot_surf, fullFilename.c_str());
 456       log_debug << "Wrote screenshot to \"" << fullFilename << "\"" << std::endl;
 457       SDL_FreeSurface(shot_surf);
 458       return;
 459     }
 460   }
 461   log_warning << "Did not save screenshot, because all files up to \"" << fullFilename << "\" already existed" << std::endl;
 462   SDL_FreeSurface(shot_surf);
 463 }
 464
 465 void
 466 GLRenderer::flip()
 467 {
 468   assert_gl("drawing");
 469   SDL_GL_SwapWindow(window);
 470 }
 471
 472 void
 473 GLRenderer::resize(int w, int h)
 474 {
 475 #ifdef OLD_SDL1
 476   SDL_CreateWindow(SDL_GL_CreateContext(w, h, 0, SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE));
 477 #endif
 478
 479   g_config->window_size = Size(w, h);
 480
 481   apply_config();
 482 }
 483
 484 void
 485 GLRenderer::apply_config()
 486 {
 487   if (false)
 488   {
 489     log_info << "Applying Config:"
 490              << "\n  Desktop: " << desktop_size.width << "x" << desktop_size.height
 491              << "\n  Window:  " << g_config->window_size
 492              << "\n  FullRes: " << g_config->fullscreen_size
 493              << "\n  Aspect:  " << g_config->aspect_size
 494              << "\n  Magnif:  " << g_config->magnification
 495              << std::endl;
 496   }
 497
 498   float target_aspect = static_cast<float>(desktop_size.width) / static_cast<float>(desktop_size.height);
 499   if (g_config->aspect_size != Size(0, 0))
 500   {
 501     target_aspect = float(g_config->aspect_size.width) / float(g_config->aspect_size.height);
 502   }
 503
 504   float desktop_aspect = 4.0f / 3.0f; // random default fallback guess
 505   if (desktop_size.width != -1 && desktop_size.height != -1)
 506   {
 507     desktop_aspect = float(desktop_size.width) / float(desktop_size.height);
 508   }
 509
 510   Size screen_size;
 511
 512   // Get the screen width
 513   if (g_config->use_fullscreen)
 514   {
 515     screen_size = g_config->fullscreen_size;
 516     desktop_aspect = float(screen_size.width) / float(screen_size.height);
 517   }
 518   else
 519   {
 520     screen_size = g_config->window_size;
 521   }
 522
 523   apply_video_mode(screen_size, g_config->use_fullscreen);
 524
 525   if (target_aspect > 1.0f)
 526   {
 527     SCREEN_WIDTH  = static_cast<int>(screen_size.width * (target_aspect / desktop_aspect));
 528     SCREEN_HEIGHT = static_cast<int>(screen_size.height);
 529   }
 530   else
 531   {
 532     SCREEN_WIDTH  = static_cast<int>(screen_size.width);
 533     SCREEN_HEIGHT = static_cast<int>(screen_size.height  * (target_aspect / desktop_aspect));
 534   }
 535
 536   Size max_size(1280, 800);
 537   Size min_size(640, 480);
 538
 539   if (g_config->magnification == 0.0f) // Magic value that means 'minfill'
 540   {
 541     // This scales SCREEN_WIDTH/SCREEN_HEIGHT so that they never excede
 542     // max_size.width/max_size.height resp. min_size.width/min_size.height
 543     if (SCREEN_WIDTH > max_size.width || SCREEN_HEIGHT > max_size.height)
 544     {
 545       float scale1  = float(max_size.width)/SCREEN_WIDTH;
 546       float scale2  = float(max_size.height)/SCREEN_HEIGHT;
 547       float scale   = (scale1 < scale2) ? scale1 : scale2;
 548       SCREEN_WIDTH  = static_cast<int>(SCREEN_WIDTH  * scale);
 549       SCREEN_HEIGHT = static_cast<int>(SCREEN_HEIGHT * scale);
 550     }
 551     else if (SCREEN_WIDTH < min_size.width || SCREEN_HEIGHT < min_size.height)
 552     {
 553       float scale1  = float(min_size.width)/SCREEN_WIDTH;
 554       float scale2  = float(min_size.height)/SCREEN_HEIGHT;
 555       float scale   = (scale1 < scale2) ? scale1 : scale2;
 556       SCREEN_WIDTH  = static_cast<int>(SCREEN_WIDTH  * scale);
 557       SCREEN_HEIGHT = static_cast<int>(SCREEN_HEIGHT * scale);
 558     }
 559
 560
 561     glViewport(0, 0, screen_size.width, screen_size.height);
 562   }
 563   else
 564   {
 565     SCREEN_WIDTH  = static_cast<int>(SCREEN_WIDTH  / g_config->magnification);
 566     SCREEN_HEIGHT = static_cast<int>(SCREEN_HEIGHT / g_config->magnification);
 567
 568     // This works by adding black borders around the screen to limit
 569     // SCREEN_WIDTH/SCREEN_HEIGHT to max_size.width/max_size.height
 570     Size new_size = screen_size;
 571
 572     if (SCREEN_WIDTH > max_size.width)
 573     {
 574       new_size.width = static_cast<int>((float) new_size.width * float(max_size.width)/SCREEN_WIDTH);
 575       SCREEN_WIDTH = static_cast<int>(max_size.width);
 576     }
 577
 578     if (SCREEN_HEIGHT > max_size.height)
 579     {
 580       new_size.height = static_cast<int>((float) new_size.height * float(max_size.height)/SCREEN_HEIGHT);
 581       SCREEN_HEIGHT = static_cast<int>(max_size.height);
 582     }
 583
 584     // Clear both buffers so that we get a clean black border without junk
 585     glClear(GL_COLOR_BUFFER_BIT);
 586     SDL_GL_SwapWindow(window);
 587     glClear(GL_COLOR_BUFFER_BIT);
 588     SDL_GL_SwapWindow(window);
 589
 590     glViewport(std::max(0, (screen_size.width  - new_size.width)  / 2),
 591                std::max(0, (screen_size.height - new_size.height) / 2),
 592                std::min(new_size.width,  screen_size.width),
 593                std::min(new_size.height, screen_size.height));
 594   }
 595
 596   glMatrixMode(GL_PROJECTION);
 597   glLoadIdentity();
 598
 599   glOrtho(0, SCREEN_WIDTH, SCREEN_HEIGHT, 0, -1, 1);
 600
 601   glMatrixMode(GL_MODELVIEW);
 602   glLoadIdentity();
 603   glTranslatef(0, 0, 0);
 604   check_gl_error("Setting up view matrices");
 605 }
 606
 607 void
 608 GLRenderer::apply_video_mode(const Size& size, bool fullscreen)
 609 {
 610   // Only change video mode when its different from the current one
 611   if (screen_size != size || fullscreen_active != fullscreen)
 612   {
 613     int flags = SDL_WINDOW_OPENGL;
 614
 615     if (fullscreen)
 616     {
 617       flags |= SDL_WINDOW_FULLSCREEN;
 618     }
 619     else
 620     {
 621       flags |= SDL_WINDOW_RESIZABLE;
 622     }
 623
 624     window = SDL_CreateWindow("SuperTux",
 625                               SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
 626                               size.width, size.height,
 627                               flags);
 628     if (!window)
 629     {
 630       std::ostringstream msg;
 631       msg << "Couldn't set video mode " << size.width << "x" << size.height << ": " << SDL_GetError();
 632       throw std::runtime_error(msg.str());
 633     }
 634     else
 635     {
 636       glcontext = SDL_GL_CreateContext(window);
 637       screen_size = size;
 638       fullscreen_active = fullscreen;
 639     }
 640   }
 641 }
 642
 643 void
 644 GLRenderer::set_gamma(float gamma)
 645 {
 646   Uint16 ramp[256];
 647   SDL_CalculateGammaRamp(gamma, ramp);
 648   SDL_SetWindowGammaRamp(window, ramp, ramp, ramp);
 649 }
 650
 651 /* EOF */