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_DIV;
 277   //TODO:this works when playing with 800x600 otherwise posY is wrong
 278   float posY = screen->h - request.pos.y / LIGHTMAP_DIV;
 279   glReadPixels((GLint) posX, (GLint) posY , 1, 1, GL_RGB, GL_FLOAT, pixels);
 280     *(getlightrequest->color_ptr) = Color( pixels[0], pixels[1], pixels[2]);
 281   //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]);
 282
 283   delete getlightrequest;
 284 }
 285
 286 void
 287 DrawingContext::draw_surface_part(DrawingRequest& request)
 288 {
 289   SurfacePartRequest* surfacepartrequest
 290     = (SurfacePartRequest*) request.request_data;
 291
 292   surfacepartrequest->surface->draw_part(
 293       surfacepartrequest->source.x, surfacepartrequest->source.y,
 294       request.pos.x, request.pos.y,
 295       surfacepartrequest->size.x, surfacepartrequest->size.y,
 296       request.alpha, request.drawing_effect);
 297
 298   delete surfacepartrequest;
 299 }
 300
 301 void
 302 DrawingContext::draw_gradient(DrawingRequest& request)
 303 {
 304   GradientRequest* gradientrequest = (GradientRequest*) request.request_data;
 305   const Color& top = gradientrequest->top;
 306   const Color& bottom = gradientrequest->bottom;
 307
 308   glDisable(GL_TEXTURE_2D);
 309   glBegin(GL_QUADS);
 310   glColor4f(top.red, top.green, top.blue, top.alpha);
 311   glVertex2f(0, 0);
 312   glVertex2f(SCREEN_WIDTH, 0);
 313   glColor4f(bottom.red, bottom.green, bottom.blue, bottom.alpha);
 314   glVertex2f(SCREEN_WIDTH, SCREEN_HEIGHT);
 315   glVertex2f(0, SCREEN_HEIGHT);
 316   glEnd();
 317   glEnable(GL_TEXTURE_2D);
 318
 319   delete gradientrequest;
 320 }
 321
 322 void
 323 DrawingContext::draw_text(DrawingRequest& request)
 324 {
 325   TextRequest* textrequest = (TextRequest*) request.request_data;
 326
 327   textrequest->font->draw(textrequest->text, request.pos,
 328       textrequest->alignment, request.drawing_effect, request.alpha);
 329
 330   delete textrequest;
 331 }
 332
 333 void
 334 DrawingContext::draw_filled_rect(DrawingRequest& request)
 335 {
 336   FillRectRequest* fillrectrequest = (FillRectRequest*) request.request_data;
 337
 338   float x = request.pos.x;
 339   float y = request.pos.y;
 340   float w = fillrectrequest->size.x;
 341   float h = fillrectrequest->size.y;
 342
 343   glDisable(GL_TEXTURE_2D);
 344   glColor4f(fillrectrequest->color.red, fillrectrequest->color.green,
 345             fillrectrequest->color.blue, fillrectrequest->color.alpha);
 346
 347   glBegin(GL_QUADS);
 348   glVertex2f(x, y);
 349   glVertex2f(x+w, y);
 350   glVertex2f(x+w, y+h);
 351   glVertex2f(x, y+h);
 352   glEnd();
 353   glEnable(GL_TEXTURE_2D);
 354
 355   delete fillrectrequest;
 356 }
 357
 358 void
 359 DrawingContext::draw_lightmap(DrawingRequest& request)
 360 {
 361   const Texture* texture = reinterpret_cast<Texture*> (request.request_data);
 362
 363   // multiple the lightmap with the framebuffer
 364   glBlendFunc(GL_DST_COLOR, GL_ZERO);
 365
 366   glBindTexture(GL_TEXTURE_2D, texture->get_handle());
 367   glBegin(GL_QUADS);
 368
 369   glTexCoord2f(0, lightmap_uv_bottom);
 370   glVertex2f(0, 0);
 371
 372   glTexCoord2f(lightmap_uv_right, lightmap_uv_bottom);
 373   glVertex2f(SCREEN_WIDTH, 0);
 374
 375   glTexCoord2f(lightmap_uv_right, 0);
 376   glVertex2f(SCREEN_WIDTH, SCREEN_HEIGHT);
 377
 378   glTexCoord2f(0, 0);
 379   glVertex2f(0, SCREEN_HEIGHT);
 380
 381   glEnd();
 382
 383   glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 384 }
 385
 386 void
 387 DrawingContext::do_drawing()
 388 {
 389 #ifdef DEBUG
 390   assert(transformstack.empty());
 391   assert(target_stack.empty());
 392 #endif
 393   transformstack.clear();
 394   target_stack.clear();
 395
 396   //Use Lightmap if ambient color is not white.
 397   bool use_lightmap = ( ambient_color.red != 1.0f   || ambient_color.green != 1.0f ||
 398                         ambient_color.blue  != 1.0f );
 399
 400   // PART1: create lightmap
 401   if(use_lightmap) {
 402     glViewport(0, screen->h - lightmap_height, lightmap_width, lightmap_height);
 403     glMatrixMode(GL_PROJECTION);
 404     glLoadIdentity();
 405     glOrtho(0, SCREEN_WIDTH, SCREEN_HEIGHT, 0, -1.0, 1.0);
 406     glMatrixMode(GL_MODELVIEW);
 407     glLoadIdentity();
 408
 409     glClearColor( ambient_color.red, ambient_color.green, ambient_color.blue, 1 );
 410     glClear(GL_COLOR_BUFFER_BIT);
 411     handle_drawing_requests(lightmap_requests);
 412     lightmap_requests.clear();
 413
 414     glDisable(GL_BLEND);
 415     glBindTexture(GL_TEXTURE_2D, lightmap->get_handle());
 416     glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, screen->h - lightmap_height, lightmap_width, lightmap_height);
 417
 418     glViewport(0, 0, screen->w, screen->h);
 419     glMatrixMode(GL_PROJECTION);
 420     glLoadIdentity();
 421     glOrtho(0, SCREEN_WIDTH, SCREEN_HEIGHT, 0, -1.0, 1.0);
 422     glMatrixMode(GL_MODELVIEW);
 423     glLoadIdentity();
 424     glEnable(GL_BLEND);
 425
 426     // add a lightmap drawing request into the queue
 427     DrawingRequest request;
 428     request.type = LIGHTMAPREQUEST;
 429     request.layer = LAYER_HUD - 1;
 430     request.request_data = lightmap;
 431     requests->push_back(request);
 432   }
 433
 434   //glClear(GL_COLOR_BUFFER_BIT);
 435   handle_drawing_requests(drawing_requests);
 436   drawing_requests.clear();
 437   assert_gl("drawing");
 438
 439   SDL_GL_SwapBuffers();
 440 }
 441
 442 void
 443 DrawingContext::handle_drawing_requests(DrawingRequests& requests)
 444 {
 445   std::stable_sort(requests.begin(), requests.end());
 446
 447   for(DrawingRequests::iterator i = requests.begin();
 448       i != requests.end(); ++i) {
 449     switch(i->type) {
 450       case SURFACE:
 451       {
 452         const Surface* surface = (const Surface*) i->request_data;
 453         if (i->angle == 0.0f &&
 454             i->color.red == 1.0f && i->color.green == 1.0f  &&
 455             i->color.blue == 1.0f &&  i->color.alpha == 1.0f  )
 456           surface->draw(i->pos.x, i->pos.y, i->alpha, i->drawing_effect);
 457         else
 458           surface->draw(i->pos.x, i->pos.y, i->alpha, i->angle, i->color, i->blend, i->drawing_effect);
 459         break;
 460       }
 461       case SURFACE_PART:
 462         draw_surface_part(*i);
 463         break;
 464       case GRADIENT:
 465         draw_gradient(*i);
 466         break;
 467       case TEXT:
 468         draw_text(*i);
 469         break;
 470       case FILLRECT:
 471         draw_filled_rect(*i);
 472         break;
 473       case LIGHTMAPREQUEST:
 474         draw_lightmap(*i);
 475         break;
 476       case GETLIGHT:
 477         get_light(*i);
 478         break;
 479     }
 480   }
 481 }
 482
 483 void
 484 DrawingContext::push_transform()
 485 {
 486   transformstack.push_back(transform);
 487 }
 488
 489 void
 490 DrawingContext::pop_transform()
 491 {
 492   assert(!transformstack.empty());
 493
 494   transform = transformstack.back();
 495   transformstack.pop_back();
 496 }
 497
 498 void
 499 DrawingContext::set_drawing_effect(DrawingEffect effect)
 500 {
 501   transform.drawing_effect = effect;
 502 }
 503
 504 DrawingEffect
 505 DrawingContext::get_drawing_effect() const
 506 {
 507   return transform.drawing_effect;
 508 }
 509
 510 void
 511 DrawingContext::set_alpha(float alpha)
 512 {
 513   transform.alpha = alpha;
 514 }
 515
 516 float
 517 DrawingContext::get_alpha() const
 518 {
 519   return transform.alpha;
 520 }
 521
 522 void
 523 DrawingContext::push_target()
 524 {
 525   target_stack.push_back(target);
 526 }
 527
 528 void
 529 DrawingContext::pop_target()
 530 {
 531   set_target(target_stack.back());
 532   target_stack.pop_back();
 533 }
 534
 535 void
 536 DrawingContext::set_target(Target target)
 537 {
 538   this->target = target;
 539   if(target == LIGHTMAP)
 540     requests = &lightmap_requests;
 541   else
 542     requests = &drawing_requests;
 543 }
 544
 545 void
 546 DrawingContext::set_ambient_color( Color new_color )
 547 {
 548   ambient_color = new_color;
 549 }