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 4
  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   DrawingRequest request;
 249   request.type = GETLIGHT;
 250   request.pos = transform.apply(position);
 251   request.layer = LAYER_GUI; //make sure all get_light requests are handled last.
 252
 253   GetLightRequest* getlightrequest = new GetLightRequest;
 254   getlightrequest->color_ptr = color;
 255   request.request_data = getlightrequest;
 256   lightmap_requests.push_back(request);
 257 }
 258
 259 void
 260 DrawingContext::get_light(DrawingRequest& request)
 261 {
 262   GetLightRequest* getlightrequest = (GetLightRequest*) request.request_data;
 263
 264   float pixels[3];
 265   for( int i = 0; i<3; i++)
 266     pixels[i] = 0.0f; //set to black
 267
 268   //TODO: hacky. Make coordinate conversion more generic
 269   glReadPixels((GLint) request.pos.x / 4, 600-(GLint)request.pos.y / 4, 1, 1, GL_RGB, GL_FLOAT, pixels);
 270   *(getlightrequest->color_ptr) = Color( pixels[0], pixels[1], pixels[2]);
 271   //printf("get_light %f/%f r%f g%f b%f\n", request.pos.x, request.pos.y, pixels[0], pixels[1], pixels[2]);
 272
 273   delete getlightrequest;
 274 }
 275
 276 void
 277 DrawingContext::draw_surface_part(DrawingRequest& request)
 278 {
 279   SurfacePartRequest* surfacepartrequest
 280     = (SurfacePartRequest*) request.request_data;
 281
 282   surfacepartrequest->surface->draw_part(
 283       surfacepartrequest->source.x, surfacepartrequest->source.y,
 284       request.pos.x, request.pos.y,
 285       surfacepartrequest->size.x, surfacepartrequest->size.y,
 286       request.alpha, request.drawing_effect);
 287
 288   delete surfacepartrequest;
 289 }
 290
 291 void
 292 DrawingContext::draw_gradient(DrawingRequest& request)
 293 {
 294   GradientRequest* gradientrequest = (GradientRequest*) request.request_data;
 295   const Color& top = gradientrequest->top;
 296   const Color& bottom = gradientrequest->bottom;
 297
 298   glDisable(GL_TEXTURE_2D);
 299   glBegin(GL_QUADS);
 300   glColor4f(top.red, top.green, top.blue, top.alpha);
 301   glVertex2f(0, 0);
 302   glVertex2f(SCREEN_WIDTH, 0);
 303   glColor4f(bottom.red, bottom.green, bottom.blue, bottom.alpha);
 304   glVertex2f(SCREEN_WIDTH, SCREEN_HEIGHT);
 305   glVertex2f(0, SCREEN_HEIGHT);
 306   glEnd();
 307   glEnable(GL_TEXTURE_2D);
 308
 309   delete gradientrequest;
 310 }
 311
 312 void
 313 DrawingContext::draw_text(DrawingRequest& request)
 314 {
 315   TextRequest* textrequest = (TextRequest*) request.request_data;
 316
 317   textrequest->font->draw(textrequest->text, request.pos,
 318       textrequest->alignment, request.drawing_effect, request.alpha);
 319
 320   delete textrequest;
 321 }
 322
 323 void
 324 DrawingContext::draw_filled_rect(DrawingRequest& request)
 325 {
 326   FillRectRequest* fillrectrequest = (FillRectRequest*) request.request_data;
 327
 328   float x = request.pos.x;
 329   float y = request.pos.y;
 330   float w = fillrectrequest->size.x;
 331   float h = fillrectrequest->size.y;
 332
 333   glDisable(GL_TEXTURE_2D);
 334   glColor4f(fillrectrequest->color.red, fillrectrequest->color.green,
 335             fillrectrequest->color.blue, fillrectrequest->color.alpha);
 336
 337   glBegin(GL_QUADS);
 338   glVertex2f(x, y);
 339   glVertex2f(x+w, y);
 340   glVertex2f(x+w, y+h);
 341   glVertex2f(x, y+h);
 342   glEnd();
 343   glEnable(GL_TEXTURE_2D);
 344
 345   delete fillrectrequest;
 346 }
 347
 348 void
 349 DrawingContext::draw_lightmap(DrawingRequest& request)
 350 {
 351   const Texture* texture = reinterpret_cast<Texture*> (request.request_data);
 352
 353   // multiple the lightmap with the framebuffer
 354   glBlendFunc(GL_DST_COLOR, GL_ZERO);
 355
 356   glBindTexture(GL_TEXTURE_2D, texture->get_handle());
 357   glBegin(GL_QUADS);
 358
 359   glTexCoord2f(0, lightmap_uv_bottom);
 360   glVertex2f(0, 0);
 361
 362   glTexCoord2f(lightmap_uv_right, lightmap_uv_bottom);
 363   glVertex2f(SCREEN_WIDTH, 0);
 364
 365   glTexCoord2f(lightmap_uv_right, 0);
 366   glVertex2f(SCREEN_WIDTH, SCREEN_HEIGHT);
 367
 368   glTexCoord2f(0, 0);
 369   glVertex2f(0, SCREEN_HEIGHT);
 370
 371   glEnd();
 372
 373   glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 374 }
 375
 376 void
 377 DrawingContext::do_drawing()
 378 {
 379 #ifdef DEBUG
 380   assert(transformstack.empty());
 381   assert(target_stack.empty());
 382 #endif
 383   transformstack.clear();
 384   target_stack.clear();
 385
 386   //Use Lightmap if ambient color is not white.
 387   bool use_lightmap = ( ambient_color.red != 1.0f   || ambient_color.green != 1.0f ||
 388                         ambient_color.blue  != 1.0f );
 389
 390   // PART1: create lightmap
 391   if(use_lightmap) {
 392     glViewport(0, screen->h - lightmap_height, lightmap_width, lightmap_height);
 393     glMatrixMode(GL_PROJECTION);
 394     glLoadIdentity();
 395     glOrtho(0, SCREEN_WIDTH, SCREEN_HEIGHT, 0, -1.0, 1.0);
 396     glMatrixMode(GL_MODELVIEW);
 397     glLoadIdentity();
 398
 399     glClearColor( ambient_color.red, ambient_color.green, ambient_color.blue, 1 );
 400     glClear(GL_COLOR_BUFFER_BIT);
 401     handle_drawing_requests(lightmap_requests);
 402     lightmap_requests.clear();
 403
 404     glDisable(GL_BLEND);
 405     glBindTexture(GL_TEXTURE_2D, lightmap->get_handle());
 406     glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, screen->h - lightmap_height, lightmap_width, lightmap_height);
 407
 408     glViewport(0, 0, screen->w, screen->h);
 409     glMatrixMode(GL_PROJECTION);
 410     glLoadIdentity();
 411     glOrtho(0, SCREEN_WIDTH, SCREEN_HEIGHT, 0, -1.0, 1.0);
 412     glMatrixMode(GL_MODELVIEW);
 413     glLoadIdentity();
 414     glEnable(GL_BLEND);
 415
 416     // add a lightmap drawing request into the queue
 417     DrawingRequest request;
 418     request.type = LIGHTMAPREQUEST;
 419     request.layer = LAYER_HUD - 1;
 420     request.request_data = lightmap;
 421     requests->push_back(request);
 422   }
 423
 424   //glClear(GL_COLOR_BUFFER_BIT);
 425   handle_drawing_requests(drawing_requests);
 426   drawing_requests.clear();
 427   assert_gl("drawing");
 428
 429   SDL_GL_SwapBuffers();
 430 }
 431
 432 void
 433 DrawingContext::handle_drawing_requests(DrawingRequests& requests)
 434 {
 435   std::stable_sort(requests.begin(), requests.end());
 436
 437   for(DrawingRequests::iterator i = requests.begin();
 438       i != requests.end(); ++i) {
 439     switch(i->type) {
 440       case SURFACE:
 441       {
 442         const Surface* surface = (const Surface*) i->request_data;
 443         surface->draw(i->pos.x, i->pos.y, i->alpha, i->angle, i->color, i->blend, i->drawing_effect);
 444         break;
 445       }
 446       case SURFACE_PART:
 447         draw_surface_part(*i);
 448         break;
 449       case GRADIENT:
 450         draw_gradient(*i);
 451         break;
 452       case TEXT:
 453         draw_text(*i);
 454         break;
 455       case FILLRECT:
 456         draw_filled_rect(*i);
 457         break;
 458       case LIGHTMAPREQUEST:
 459         draw_lightmap(*i);
 460         break;
 461       case GETLIGHT:
 462         get_light(*i);
 463         break;
 464     }
 465   }
 466 }
 467
 468 void
 469 DrawingContext::push_transform()
 470 {
 471   transformstack.push_back(transform);
 472 }
 473
 474 void
 475 DrawingContext::pop_transform()
 476 {
 477   assert(!transformstack.empty());
 478
 479   transform = transformstack.back();
 480   transformstack.pop_back();
 481 }
 482
 483 void
 484 DrawingContext::set_drawing_effect(DrawingEffect effect)
 485 {
 486   transform.drawing_effect = effect;
 487 }
 488
 489 DrawingEffect
 490 DrawingContext::get_drawing_effect() const
 491 {
 492   return transform.drawing_effect;
 493 }
 494
 495 void
 496 DrawingContext::set_alpha(float alpha)
 497 {
 498   transform.alpha = alpha;
 499 }
 500
 501 float
 502 DrawingContext::get_alpha() const
 503 {
 504   return transform.alpha;
 505 }
 506
 507 void
 508 DrawingContext::push_target()
 509 {
 510   target_stack.push_back(target);
 511 }
 512
 513 void
 514 DrawingContext::pop_target()
 515 {
 516   set_target(target_stack.back());
 517   target_stack.pop_back();
 518 }
 519
 520 void
 521 DrawingContext::set_target(Target target)
 522 {
 523   this->target = target;
 524   if(target == LIGHTMAP)
 525     requests = &lightmap_requests;
 526   else
 527     requests = &drawing_requests;
 528 }
 529
 530 void
 531 DrawingContext::set_ambient_color( Color new_color )
 532 {
 533   ambient_color = new_color;
 534 }