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 #define LIGHTMAP_DIV 5
  37
  38 static inline int next_po2(int val)
  39 {
  40   int result = 1;
  41   while(result < val)
  42     result *= 2;
  43
  44   return result;
  45 }
  46
  47 DrawingContext::DrawingContext()
  48   : ambient_color( 1.0f, 1.0f, 1.0f, 1.0f )
  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::get_light(const Vector& position, Color* color)
 242 {
 243   if( ambient_color.red == 1.0f && ambient_color.green == 1.0f
 244       && ambient_color.blue  == 1.0f ) {
 245     *color = Color( 1.0f, 1.0f, 1.0f);
 246     return;
 247   }
 248
 249   DrawingRequest request;
 250   request.type = GETLIGHT;
 251   request.pos = transform.apply(position);
 252
 253   //There is no light offscreen.
 254   if(request.pos.x >= SCREEN_WIDTH || request.pos.y >= SCREEN_HEIGHT
 255       || request.pos.x < 0 || request.pos.y < 0){
 256     *color = Color( 0, 0, 0);
 257     return;
 258   }
 259
 260   request.layer = LAYER_GUI; //make sure all get_light requests are handled last.
 261   GetLightRequest* getlightrequest = new GetLightRequest;
 262   getlightrequest->color_ptr = color;
 263   request.request_data = getlightrequest;
 264   lightmap_requests.push_back(request);
 265 }
 266
 267 void
 268 DrawingContext::get_light(DrawingRequest& request)
 269 {
 270   GetLightRequest* getlightrequest = (GetLightRequest*) request.request_data;
 271
 272   float pixels[3];
 273   for( int i = 0; i<3; i++)
 274     pixels[i] = 0.0f; //set to black
 275
 276   float posX = request.pos.x * lightmap_width / SCREEN_WIDTH;
 277   float posY = screen->h - request.pos.y * lightmap_height / SCREEN_HEIGHT;
 278   glReadPixels((GLint) posX, (GLint) posY , 1, 1, GL_RGB, GL_FLOAT, pixels);
 279     *(getlightrequest->color_ptr) = Color( pixels[0], pixels[1], pixels[2]);
 280   //printf("get_light %f/%f =>%f/%f r%f g%f b%f\n", request.pos.x, request.pos.y, posX, posY, pixels[0], pixels[1], pixels[2]);
 281
 282   delete getlightrequest;
 283 }
 284
 285 void
 286 DrawingContext::draw_surface_part(DrawingRequest& request)
 287 {
 288   SurfacePartRequest* surfacepartrequest
 289     = (SurfacePartRequest*) request.request_data;
 290
 291   surfacepartrequest->surface->draw_part(
 292       surfacepartrequest->source.x, surfacepartrequest->source.y,
 293       request.pos.x, request.pos.y,
 294       surfacepartrequest->size.x, surfacepartrequest->size.y,
 295       request.alpha, request.drawing_effect);
 296
 297   delete surfacepartrequest;
 298 }
 299
 300 void
 301 DrawingContext::draw_gradient(DrawingRequest& request)
 302 {
 303   GradientRequest* gradientrequest = (GradientRequest*) request.request_data;
 304   const Color& top = gradientrequest->top;
 305   const Color& bottom = gradientrequest->bottom;
 306
 307   glDisable(GL_TEXTURE_2D);
 308   glBegin(GL_QUADS);
 309   glColor4f(top.red, top.green, top.blue, top.alpha);
 310   glVertex2f(0, 0);
 311   glVertex2f(SCREEN_WIDTH, 0);
 312   glColor4f(bottom.red, bottom.green, bottom.blue, bottom.alpha);
 313   glVertex2f(SCREEN_WIDTH, SCREEN_HEIGHT);
 314   glVertex2f(0, SCREEN_HEIGHT);
 315   glEnd();
 316   glEnable(GL_TEXTURE_2D);
 317
 318   delete gradientrequest;
 319 }
 320
 321 void
 322 DrawingContext::draw_text(DrawingRequest& request)
 323 {
 324   TextRequest* textrequest = (TextRequest*) request.request_data;
 325
 326   textrequest->font->draw(textrequest->text, request.pos,
 327       textrequest->alignment, request.drawing_effect, request.alpha);
 328
 329   delete textrequest;
 330 }
 331
 332 void
 333 DrawingContext::draw_filled_rect(DrawingRequest& request)
 334 {
 335   FillRectRequest* fillrectrequest = (FillRectRequest*) request.request_data;
 336
 337   float x = request.pos.x;
 338   float y = request.pos.y;
 339   float w = fillrectrequest->size.x;
 340   float h = fillrectrequest->size.y;
 341
 342   glDisable(GL_TEXTURE_2D);
 343   glColor4f(fillrectrequest->color.red, fillrectrequest->color.green,
 344             fillrectrequest->color.blue, fillrectrequest->color.alpha);
 345
 346   glBegin(GL_QUADS);
 347   glVertex2f(x, y);
 348   glVertex2f(x+w, y);
 349   glVertex2f(x+w, y+h);
 350   glVertex2f(x, y+h);
 351   glEnd();
 352   glEnable(GL_TEXTURE_2D);
 353
 354   delete fillrectrequest;
 355 }
 356
 357 void
 358 DrawingContext::draw_lightmap(DrawingRequest& request)
 359 {
 360   const Texture* texture = reinterpret_cast<Texture*> (request.request_data);
 361
 362   // multiple the lightmap with the framebuffer
 363   glBlendFunc(GL_DST_COLOR, GL_ZERO);
 364
 365   glBindTexture(GL_TEXTURE_2D, texture->get_handle());
 366   glBegin(GL_QUADS);
 367
 368   glTexCoord2f(0, lightmap_uv_bottom);
 369   glVertex2f(0, 0);
 370
 371   glTexCoord2f(lightmap_uv_right, lightmap_uv_bottom);
 372   glVertex2f(SCREEN_WIDTH, 0);
 373
 374   glTexCoord2f(lightmap_uv_right, 0);
 375   glVertex2f(SCREEN_WIDTH, SCREEN_HEIGHT);
 376
 377   glTexCoord2f(0, 0);
 378   glVertex2f(0, SCREEN_HEIGHT);
 379
 380   glEnd();
 381
 382   glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 383 }
 384
 385 void
 386 DrawingContext::do_drawing()
 387 {
 388 #ifdef DEBUG
 389   assert(transformstack.empty());
 390   assert(target_stack.empty());
 391 #endif
 392   transformstack.clear();
 393   target_stack.clear();
 394
 395   //Use Lightmap if ambient color is not white.
 396   bool use_lightmap = ( ambient_color.red != 1.0f   || ambient_color.green != 1.0f ||
 397                         ambient_color.blue  != 1.0f );
 398
 399   // PART1: create lightmap
 400   if(use_lightmap) {
 401     glViewport(0, screen->h - lightmap_height, lightmap_width, lightmap_height);
 402     glMatrixMode(GL_PROJECTION);
 403     glLoadIdentity();
 404     glOrtho(0, SCREEN_WIDTH, SCREEN_HEIGHT, 0, -1.0, 1.0);
 405     glMatrixMode(GL_MODELVIEW);
 406     glLoadIdentity();
 407
 408     glClearColor( ambient_color.red, ambient_color.green, ambient_color.blue, 1 );
 409     glClear(GL_COLOR_BUFFER_BIT);
 410     handle_drawing_requests(lightmap_requests);
 411     lightmap_requests.clear();
 412
 413     glDisable(GL_BLEND);
 414     glBindTexture(GL_TEXTURE_2D, lightmap->get_handle());
 415     glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, screen->h - lightmap_height, lightmap_width, lightmap_height);
 416
 417     glViewport(0, 0, screen->w, screen->h);
 418     glMatrixMode(GL_PROJECTION);
 419     glLoadIdentity();
 420     glOrtho(0, SCREEN_WIDTH, SCREEN_HEIGHT, 0, -1.0, 1.0);
 421     glMatrixMode(GL_MODELVIEW);
 422     glLoadIdentity();
 423     glEnable(GL_BLEND);
 424
 425     // add a lightmap drawing request into the queue
 426     DrawingRequest request;
 427     request.type = LIGHTMAPREQUEST;
 428     request.layer = LAYER_HUD - 1;
 429     request.request_data = lightmap;
 430     requests->push_back(request);
 431   }
 432
 433   //glClear(GL_COLOR_BUFFER_BIT);
 434   handle_drawing_requests(drawing_requests);
 435   drawing_requests.clear();
 436   assert_gl("drawing");
 437
 438   SDL_GL_SwapBuffers();
 439 }
 440
 441 void
 442 DrawingContext::handle_drawing_requests(DrawingRequests& requests)
 443 {
 444   std::stable_sort(requests.begin(), requests.end());
 445
 446   for(DrawingRequests::iterator i = requests.begin();
 447       i != requests.end(); ++i) {
 448     switch(i->type) {
 449       case SURFACE:
 450       {
 451         const Surface* surface = (const Surface*) i->request_data;
 452         if (i->angle == 0.0f &&
 453             i->color.red == 1.0f && i->color.green == 1.0f  &&
 454             i->color.blue == 1.0f &&  i->color.alpha == 1.0f  )
 455           surface->draw(i->pos.x, i->pos.y, i->alpha, i->drawing_effect);
 456         else
 457           surface->draw(i->pos.x, i->pos.y, i->alpha, i->angle, i->color, i->blend, i->drawing_effect);
 458         break;
 459       }
 460       case SURFACE_PART:
 461         draw_surface_part(*i);
 462         break;
 463       case GRADIENT:
 464         draw_gradient(*i);
 465         break;
 466       case TEXT:
 467         draw_text(*i);
 468         break;
 469       case FILLRECT:
 470         draw_filled_rect(*i);
 471         break;
 472       case LIGHTMAPREQUEST:
 473         draw_lightmap(*i);
 474         break;
 475       case GETLIGHT:
 476         get_light(*i);
 477         break;
 478     }
 479   }
 480 }
 481
 482 void
 483 DrawingContext::push_transform()
 484 {
 485   transformstack.push_back(transform);
 486 }
 487
 488 void
 489 DrawingContext::pop_transform()
 490 {
 491   assert(!transformstack.empty());
 492
 493   transform = transformstack.back();
 494   transformstack.pop_back();
 495 }
 496
 497 void
 498 DrawingContext::set_drawing_effect(DrawingEffect effect)
 499 {
 500   transform.drawing_effect = effect;
 501 }
 502
 503 DrawingEffect
 504 DrawingContext::get_drawing_effect() const
 505 {
 506   return transform.drawing_effect;
 507 }
 508
 509 void
 510 DrawingContext::set_alpha(float alpha)
 511 {
 512   transform.alpha = alpha;
 513 }
 514
 515 float
 516 DrawingContext::get_alpha() const
 517 {
 518   return transform.alpha;
 519 }
 520
 521 void
 522 DrawingContext::push_target()
 523 {
 524   target_stack.push_back(target);
 525 }
 526
 527 void
 528 DrawingContext::pop_target()
 529 {
 530   set_target(target_stack.back());
 531   target_stack.pop_back();
 532 }
 533
 534 void
 535 DrawingContext::set_target(Target target)
 536 {
 537   this->target = target;
 538   if(target == LIGHTMAP)
 539     requests = &lightmap_requests;
 540   else
 541     requests = &drawing_requests;
 542 }
 543
 544 void
 545 DrawingContext::set_ambient_color( Color new_color )
 546 {
 547   ambient_color = new_color;
 548 }