src/video/drawing_context.cpp

   1 //  $Id$
   2 //
   3 //  SuperTux
   4 //  Copyright (C) 2006 Matthias Braun <matze@braunis.de>
   5 //
   6 //  This program is free software; you can redistribute it and/or
   7 //  modify it under the terms of the GNU General Public License
   8 //  as published by the Free Software Foundation; either version 2
   9 //  of the License, or (at your option) any later version.
  10 //
  11 //  This program is distributed in the hope that it will be useful,
  12 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 //  GNU General Public License for more details.
  15 //
  16 //  You should have received a copy of the GNU General Public License
  17 //  along with this program; if not, write to the Free Software
  18 //  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  19
  20 #include <config.h>
  21
  22 #include <algorithm>
  23 #include <cassert>
  24 #include <iostream>
  25 #include <SDL_image.h>
  26 #include <GL/gl.h>
  27
  28 #include "drawing_context.hpp"
  29 #include "surface.hpp"
  30 #include "font.hpp"
  31 #include "main.hpp"
  32 #include "gameconfig.hpp"
  33 #include "glutil.hpp"
  34 #include "texture.hpp"
  35 #include "texture_manager.hpp"
  36
  37 #define LIGHTMAP_DIV 4
  38
  39 static inline int next_po2(int val)
  40 {
  41   int result = 1;
  42   while(result < val)
  43     result *= 2;
  44
  45   return result;
  46 }
  47
  48 DrawingContext::DrawingContext()
  49 {
  50   screen = SDL_GetVideoSurface();
  51
  52   lightmap_width = screen->w / LIGHTMAP_DIV;
  53   lightmap_height = screen->h / LIGHTMAP_DIV;
  54   unsigned int width = next_po2(lightmap_width);
  55   unsigned int height = next_po2(lightmap_height);
  56
  57   lightmap = new Texture(width, height, GL_RGB);
  58
  59   lightmap_uv_right = static_cast<float>(lightmap_width) / static_cast<float>(width);
  60   lightmap_uv_bottom = static_cast<float>(lightmap_height) / static_cast<float>(height);
  61   texture_manager->register_texture(lightmap);
  62
  63   requests = &drawing_requests;
  64 }
  65
  66 DrawingContext::~DrawingContext()
  67 {
  68   texture_manager->remove_texture(lightmap);
  69   delete lightmap;
  70 }
  71
  72 void
  73 DrawingContext::draw_surface(const Surface* surface, const Vector& position,
  74                              float angle, const Color& color, const Blend& blend,
  75                              int layer)
  76 {
  77   assert(surface != 0);
  78
  79   DrawingRequest request;
  80
  81   request.type = SURFACE;
  82   request.pos = transform.apply(position);
  83
  84   if(request.pos.x >= SCREEN_WIDTH || request.pos.y >= SCREEN_HEIGHT
  85       || request.pos.x + surface->get_width() < 0
  86       || request.pos.y + surface->get_height() < 0)
  87     return;
  88
  89   request.layer = layer;
  90   request.drawing_effect = transform.drawing_effect;
  91   request.alpha = transform.alpha;
  92   request.angle = angle;
  93   request.color = color;
  94   request.blend = blend;
  95
  96   request.request_data = const_cast<Surface*> (surface);
  97
  98   requests->push_back(request);
  99 }
 100
 101 void
 102 DrawingContext::draw_surface(const Surface* surface, const Vector& position,
 103     int layer)
 104 {
 105   draw_surface(surface, position, 0.0f, Color(1.0f, 1.0f, 1.0f), Blend(), layer);
 106 }
 107
 108 void
 109 DrawingContext::draw_surface_part(const Surface* surface, const Vector& source,
 110     const Vector& size, const Vector& dest, int layer)
 111 {
 112   assert(surface != 0);
 113
 114   DrawingRequest request;
 115
 116   request.type = SURFACE_PART;
 117   request.pos = transform.apply(dest);
 118   request.layer = layer;
 119   request.drawing_effect = transform.drawing_effect;
 120   request.alpha = transform.alpha;
 121
 122   SurfacePartRequest* surfacepartrequest = new SurfacePartRequest();
 123   surfacepartrequest->size = size;
 124   surfacepartrequest->source = source;
 125   surfacepartrequest->surface = surface;
 126
 127   // clip on screen borders
 128   if(request.pos.x < 0) {
 129     surfacepartrequest->size.x += request.pos.x;
 130     if(surfacepartrequest->size.x <= 0)
 131       return;
 132     surfacepartrequest->source.x -= request.pos.x;
 133     request.pos.x = 0;
 134   }
 135   if(request.pos.y < 0) {
 136     surfacepartrequest->size.y += request.pos.y;
 137     if(surfacepartrequest->size.y <= 0)
 138       return;
 139     surfacepartrequest->source.y -= request.pos.y;
 140     request.pos.y = 0;
 141   }
 142   request.request_data = surfacepartrequest;
 143
 144   requests->push_back(request);
 145 }
 146
 147 void
 148 DrawingContext::draw_text(const Font* font, const std::string& text,
 149     const Vector& position, FontAlignment alignment, int layer)
 150 {
 151   DrawingRequest request;
 152
 153   request.type = TEXT;
 154   request.pos = transform.apply(position);
 155   request.layer = layer;
 156   request.drawing_effect = transform.drawing_effect;
 157   request.alpha = transform.alpha;
 158
 159   TextRequest* textrequest = new TextRequest;
 160   textrequest->font = font;
 161   textrequest->text = text;
 162   textrequest->alignment = alignment;
 163   request.request_data = textrequest;
 164
 165   requests->push_back(request);
 166 }
 167
 168 void
 169 DrawingContext::draw_center_text(const Font* font, const std::string& text,
 170     const Vector& position, int layer)
 171 {
 172   draw_text(font, text, Vector(position.x + SCREEN_WIDTH/2, position.y),
 173       CENTER_ALLIGN, layer);
 174 }
 175
 176 void
 177 DrawingContext::draw_gradient(const Color& top, const Color& bottom, int layer)
 178 {
 179   DrawingRequest request;
 180
 181   request.type = GRADIENT;
 182   request.pos = Vector(0,0);
 183   request.layer = layer;
 184
 185   request.drawing_effect = transform.drawing_effect;
 186   request.alpha = transform.alpha;
 187
 188   GradientRequest* gradientrequest = new GradientRequest;
 189   gradientrequest->top = top;
 190   gradientrequest->bottom = bottom;
 191   request.request_data = gradientrequest;
 192
 193   requests->push_back(request);
 194 }
 195
 196 void
 197 DrawingContext::draw_filled_rect(const Vector& topleft, const Vector& size,
 198                                  const Color& color, int layer)
 199 {
 200   DrawingRequest request;
 201
 202   request.type = FILLRECT;
 203   request.pos = transform.apply(topleft);
 204   request.layer = layer;
 205
 206   request.drawing_effect = transform.drawing_effect;
 207   request.alpha = transform.alpha;
 208
 209   FillRectRequest* fillrectrequest = new FillRectRequest;
 210   fillrectrequest->size = size;
 211   fillrectrequest->color = color;
 212   fillrectrequest->color.alpha = color.alpha * transform.alpha;
 213   request.request_data = fillrectrequest;
 214
 215   requests->push_back(request);
 216 }
 217
 218 void
 219 DrawingContext::draw_filled_rect(const Rect& rect, const Color& color,
 220                                  int layer)
 221 {
 222   DrawingRequest request;
 223
 224   request.type = FILLRECT;
 225   request.pos = transform.apply(rect.p1);
 226   request.layer = layer;
 227
 228   request.drawing_effect = transform.drawing_effect;
 229   request.alpha = transform.alpha;
 230
 231   FillRectRequest* fillrectrequest = new FillRectRequest;
 232   fillrectrequest->size = Vector(rect.get_width(), rect.get_height());
 233   fillrectrequest->color = color;
 234   fillrectrequest->color.alpha = color.alpha * transform.alpha;
 235   request.request_data = fillrectrequest;
 236
 237   requests->push_back(request);
 238 }
 239
 240 void
 241 DrawingContext::draw_surface_part(DrawingRequest& request)
 242 {
 243   SurfacePartRequest* surfacepartrequest
 244     = (SurfacePartRequest*) request.request_data;
 245
 246   surfacepartrequest->surface->draw_part(
 247       surfacepartrequest->source.x, surfacepartrequest->source.y,
 248       request.pos.x, request.pos.y,
 249       surfacepartrequest->size.x, surfacepartrequest->size.y,
 250       request.alpha, request.drawing_effect);
 251
 252   delete surfacepartrequest;
 253 }
 254
 255 void
 256 DrawingContext::draw_gradient(DrawingRequest& request)
 257 {
 258   GradientRequest* gradientrequest = (GradientRequest*) request.request_data;
 259   const Color& top = gradientrequest->top;
 260   const Color& bottom = gradientrequest->bottom;
 261
 262   glDisable(GL_TEXTURE_2D);
 263   glBegin(GL_QUADS);
 264   glColor4f(top.red, top.green, top.blue, top.alpha);
 265   glVertex2f(0, 0);
 266   glVertex2f(SCREEN_WIDTH, 0);
 267   glColor4f(bottom.red, bottom.green, bottom.blue, bottom.alpha);
 268   glVertex2f(SCREEN_WIDTH, SCREEN_HEIGHT);
 269   glVertex2f(0, SCREEN_HEIGHT);
 270   glEnd();
 271   glEnable(GL_TEXTURE_2D);
 272
 273   delete gradientrequest;
 274 }
 275
 276 void
 277 DrawingContext::draw_text(DrawingRequest& request)
 278 {
 279   TextRequest* textrequest = (TextRequest*) request.request_data;
 280
 281   textrequest->font->draw(textrequest->text, request.pos,
 282       textrequest->alignment, request.drawing_effect, request.alpha);
 283
 284   delete textrequest;
 285 }
 286
 287 void
 288 DrawingContext::draw_filled_rect(DrawingRequest& request)
 289 {
 290   FillRectRequest* fillrectrequest = (FillRectRequest*) request.request_data;
 291
 292   float x = request.pos.x;
 293   float y = request.pos.y;
 294   float w = fillrectrequest->size.x;
 295   float h = fillrectrequest->size.y;
 296
 297   glDisable(GL_TEXTURE_2D);
 298   glColor4f(fillrectrequest->color.red, fillrectrequest->color.green,
 299             fillrectrequest->color.blue, fillrectrequest->color.alpha);
 300
 301   glBegin(GL_QUADS);
 302   glVertex2f(x, y);
 303   glVertex2f(x+w, y);
 304   glVertex2f(x+w, y+h);
 305   glVertex2f(x, y+h);
 306   glEnd();
 307   glEnable(GL_TEXTURE_2D);
 308
 309   delete fillrectrequest;
 310 }
 311
 312 void
 313 DrawingContext::do_drawing()
 314 {
 315 #ifdef DEBUG
 316   assert(transformstack.empty());
 317   assert(target_stack.empty());
 318 #endif
 319   transformstack.clear();
 320   target_stack.clear();
 321
 322   bool use_lightmap = lightmap_requests.size() != 0;
 323
 324   // PART1: create lightmap
 325   if(use_lightmap) {
 326     glViewport(0, screen->h - lightmap_height, lightmap_width, lightmap_height);
 327     glMatrixMode(GL_PROJECTION);
 328     glLoadIdentity();
 329     glOrtho(0, SCREEN_WIDTH, SCREEN_HEIGHT, 0, -1.0, 1.0);
 330     glMatrixMode(GL_MODELVIEW);
 331     glLoadIdentity();
 332
 333     // FIXME: Add ambient light support here
 334     glClearColor(0.3, 0.3, 0.4, 1);
 335     glClear(GL_COLOR_BUFFER_BIT);
 336     handle_drawing_requests(lightmap_requests);
 337     lightmap_requests.clear();
 338
 339     glDisable(GL_BLEND);
 340     glBindTexture(GL_TEXTURE_2D, lightmap->get_handle());
 341     glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, screen->h - lightmap_height, lightmap_width, lightmap_height);
 342
 343     glViewport(0, 0, screen->w, screen->h);
 344     glMatrixMode(GL_PROJECTION);
 345     glLoadIdentity();
 346     glOrtho(0, SCREEN_WIDTH, SCREEN_HEIGHT, 0, -1.0, 1.0);
 347     glMatrixMode(GL_MODELVIEW);
 348     glLoadIdentity();
 349     glEnable(GL_BLEND);
 350   }
 351
 352   //glClear(GL_COLOR_BUFFER_BIT);
 353   handle_drawing_requests(drawing_requests);
 354   drawing_requests.clear();
 355
 356   if(use_lightmap) {
 357     // multiple the lightmap with the framebuffer
 358     glBlendFunc(GL_DST_COLOR, GL_ZERO);
 359
 360     glBindTexture(GL_TEXTURE_2D, lightmap->get_handle());
 361     glBegin(GL_QUADS);
 362
 363     glTexCoord2f(0, lightmap_uv_bottom);
 364     glVertex2f(0, 0);
 365
 366     glTexCoord2f(lightmap_uv_right, lightmap_uv_bottom);
 367     glVertex2f(SCREEN_WIDTH, 0);
 368
 369     glTexCoord2f(lightmap_uv_right, 0);
 370     glVertex2f(SCREEN_WIDTH, SCREEN_HEIGHT);
 371
 372     glTexCoord2f(0, 0);
 373     glVertex2f(0, SCREEN_HEIGHT);
 374
 375     glEnd();
 376
 377     glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 378   }
 379
 380   assert_gl("drawing");
 381
 382   SDL_GL_SwapBuffers();
 383 }
 384
 385 void
 386 DrawingContext::handle_drawing_requests(DrawingRequests& requests)
 387 {
 388   std::stable_sort(requests.begin(), requests.end());
 389
 390   for(DrawingRequests::iterator i = requests.begin();
 391       i != requests.end(); ++i) {
 392     switch(i->type) {
 393       case SURFACE:
 394       {
 395         const Surface* surface = (const Surface*) i->request_data;
 396         if (i->angle == 0.0f)
 397           surface->draw(i->pos.x, i->pos.y, i->alpha, i->drawing_effect);
 398         else
 399           surface->draw(i->pos.x, i->pos.y, i->alpha, i->angle, i->color, i->blend, i->drawing_effect);
 400         break;
 401       }
 402       case SURFACE_PART:
 403         draw_surface_part(*i);
 404         break;
 405       case GRADIENT:
 406         draw_gradient(*i);
 407         break;
 408       case TEXT:
 409         draw_text(*i);
 410         break;
 411       case FILLRECT:
 412         draw_filled_rect(*i);
 413         break;
 414     }
 415   }
 416 }
 417
 418 void
 419 DrawingContext::push_transform()
 420 {
 421   transformstack.push_back(transform);
 422 }
 423
 424 void
 425 DrawingContext::pop_transform()
 426 {
 427   assert(!transformstack.empty());
 428
 429   transform = transformstack.back();
 430   transformstack.pop_back();
 431 }
 432
 433 void
 434 DrawingContext::set_drawing_effect(DrawingEffect effect)
 435 {
 436   transform.drawing_effect = effect;
 437 }
 438
 439 DrawingEffect
 440 DrawingContext::get_drawing_effect() const
 441 {
 442   return transform.drawing_effect;
 443 }
 444
 445 void
 446 DrawingContext::set_alpha(float alpha)
 447 {
 448   transform.alpha = alpha;
 449 }
 450
 451 float
 452 DrawingContext::get_alpha() const
 453 {
 454   return transform.alpha;
 455 }
 456
 457 void
 458 DrawingContext::push_target()
 459 {
 460   target_stack.push_back(target);
 461 }
 462
 463 void
 464 DrawingContext::pop_target()
 465 {
 466   set_target(target_stack.back());
 467   target_stack.pop_back();
 468 }
 469
 470 void
 471 DrawingContext::set_target(Target target)
 472 {
 473   this->target = target;
 474   if(target == LIGHTMAP)
 475     requests = &lightmap_requests;
 476   else
 477     requests = &drawing_requests;
 478 }