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 #include <config.h>
  20
  21 #include <functional>
  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 #include "obstack/obstackpp.hpp"
  37 #define LIGHTMAP_DIV 5
  38
  39 enum RequestType
  40 {
  41   SURFACE, SURFACE_PART, TEXT, GRADIENT, FILLRECT, LIGHTMAPREQUEST, GETLIGHT
  42 };
  43
  44 struct SurfacePartRequest
  45 {
  46   const Surface* surface;
  47   Vector source, size;
  48 };
  49
  50 struct TextRequest
  51 {
  52   const Font* font;
  53   std::string text;
  54   FontAlignment alignment;
  55 };
  56
  57 struct GradientRequest
  58 {
  59   Color top, bottom;
  60   Vector size;
  61 };
  62
  63 struct FillRectRequest
  64 {
  65   Color color;
  66   Vector size;
  67 };
  68
  69 struct DrawingRequest
  70 {
  71   RequestType type;
  72   Vector pos;
  73
  74   int layer;
  75   DrawingEffect drawing_effect;
  76   float alpha;
  77   Blend blend;
  78   float angle;
  79   Color color;
  80
  81   void* request_data;
  82
  83   DrawingRequest()
  84     : angle(0.0f),
  85       color(1.0f, 1.0f, 1.0f, 1.0f)
  86   {}
  87
  88   bool operator<(const DrawingRequest& other) const
  89   {
  90     return layer < other.layer;
  91   }
  92 };
  93
  94 struct GetLightRequest
  95 {
  96   Color* color_ptr;
  97 };
  98
  99 static inline int next_po2(int val)
 100 {
 101   int result = 1;
 102   while(result < val)
 103     result *= 2;
 104
 105   return result;
 106 }
 107
 108 DrawingContext::DrawingContext()
 109   : ambient_color(1.0f, 1.0f, 1.0f, 1.0f), target(NORMAL)
 110 {
 111   screen = SDL_GetVideoSurface();
 112
 113   lightmap_width = screen->w / LIGHTMAP_DIV;
 114   lightmap_height = screen->h / LIGHTMAP_DIV;
 115   unsigned int width = next_po2(lightmap_width);
 116   unsigned int height = next_po2(lightmap_height);
 117
 118   lightmap = new Texture(width, height, GL_RGB);
 119
 120   lightmap_uv_right = static_cast<float>(lightmap_width) / static_cast<float>(width);
 121   lightmap_uv_bottom = static_cast<float>(lightmap_height) / static_cast<float>(height);
 122   texture_manager->register_texture(lightmap);
 123
 124   requests = &drawing_requests;
 125
 126   obstack_init(&obst);
 127 }
 128
 129 DrawingContext::~DrawingContext()
 130 {
 131   obstack_free(&obst, NULL);
 132
 133   texture_manager->remove_texture(lightmap);
 134   delete lightmap;
 135 }
 136
 137 void
 138 DrawingContext::draw_surface(const Surface* surface, const Vector& position,
 139                              float angle, const Color& color, const Blend& blend,
 140                              int layer)
 141 {
 142   assert(surface != 0);
 143
 144   DrawingRequest* request = new(obst) DrawingRequest();
 145
 146   request->type = SURFACE;
 147   request->pos = transform.apply(position);
 148
 149   if(request->pos.x >= SCREEN_WIDTH || request->pos.y >= SCREEN_HEIGHT
 150       || request->pos.x + surface->get_width() < 0
 151       || request->pos.y + surface->get_height() < 0)
 152     return;
 153
 154   request->layer = layer;
 155   request->drawing_effect = transform.drawing_effect;
 156   request->alpha = transform.alpha;
 157   request->angle = angle;
 158   request->color = color;
 159   request->blend = blend;
 160
 161   request->request_data = const_cast<Surface*> (surface);
 162
 163   requests->push_back(request);
 164 }
 165
 166 void
 167 DrawingContext::draw_surface(const Surface* surface, const Vector& position,
 168     int layer)
 169 {
 170   draw_surface(surface, position, 0.0f, Color(1.0f, 1.0f, 1.0f), Blend(), layer);
 171 }
 172
 173 void
 174 DrawingContext::draw_surface_part(const Surface* surface, const Vector& source,
 175     const Vector& size, const Vector& dest, int layer)
 176 {
 177   assert(surface != 0);
 178
 179   DrawingRequest* request = new(obst) DrawingRequest();
 180
 181   request->type = SURFACE_PART;
 182   request->pos = transform.apply(dest);
 183   request->layer = layer;
 184   request->drawing_effect = transform.drawing_effect;
 185   request->alpha = transform.alpha;
 186
 187   SurfacePartRequest* surfacepartrequest = new(obst) SurfacePartRequest();
 188   surfacepartrequest->size = size;
 189   surfacepartrequest->source = source;
 190   surfacepartrequest->surface = surface;
 191
 192   // clip on screen borders
 193   if(request->pos.x < 0) {
 194     surfacepartrequest->size.x += request->pos.x;
 195     if(surfacepartrequest->size.x <= 0)
 196       return;
 197     surfacepartrequest->source.x -= request->pos.x;
 198     request->pos.x = 0;
 199   }
 200   if(request->pos.y < 0) {
 201     surfacepartrequest->size.y += request->pos.y;
 202     if(surfacepartrequest->size.y <= 0)
 203       return;
 204     surfacepartrequest->source.y -= request->pos.y;
 205     request->pos.y = 0;
 206   }
 207   request->request_data = surfacepartrequest;
 208
 209   requests->push_back(request);
 210 }
 211
 212 void
 213 DrawingContext::draw_text(const Font* font, const std::string& text,
 214     const Vector& position, FontAlignment alignment, int layer)
 215 {
 216   DrawingRequest* request = new(obst) DrawingRequest();
 217
 218   request->type = TEXT;
 219   request->pos = transform.apply(position);
 220   request->layer = layer;
 221   request->drawing_effect = transform.drawing_effect;
 222   request->alpha = transform.alpha;
 223
 224   TextRequest* textrequest = new(obst) TextRequest();
 225   textrequest->font = font;
 226   textrequest->text = text;
 227   textrequest->alignment = alignment;
 228   request->request_data = textrequest;
 229
 230   requests->push_back(request);
 231 }
 232
 233 void
 234 DrawingContext::draw_center_text(const Font* font, const std::string& text,
 235     const Vector& position, int layer)
 236 {
 237   draw_text(font, text, Vector(position.x + SCREEN_WIDTH/2, position.y),
 238       ALIGN_CENTER, layer);
 239 }
 240
 241 void
 242 DrawingContext::draw_gradient(const Color& top, const Color& bottom, int layer)
 243 {
 244   DrawingRequest* request = new(obst) DrawingRequest();
 245
 246   request->type = GRADIENT;
 247   request->pos = Vector(0,0);
 248   request->layer = layer;
 249
 250   request->drawing_effect = transform.drawing_effect;
 251   request->alpha = transform.alpha;
 252
 253   GradientRequest* gradientrequest = new(obst) GradientRequest();
 254   gradientrequest->top = top;
 255   gradientrequest->bottom = bottom;
 256   request->request_data = gradientrequest;
 257
 258   requests->push_back(request);
 259 }
 260
 261 void
 262 DrawingContext::draw_filled_rect(const Vector& topleft, const Vector& size,
 263                                  const Color& color, int layer)
 264 {
 265   DrawingRequest* request = new(obst) DrawingRequest();
 266
 267   request->type = FILLRECT;
 268   request->pos = transform.apply(topleft);
 269   request->layer = layer;
 270
 271   request->drawing_effect = transform.drawing_effect;
 272   request->alpha = transform.alpha;
 273
 274   FillRectRequest* fillrectrequest = new(obst) FillRectRequest();
 275   fillrectrequest->size = size;
 276   fillrectrequest->color = color;
 277   fillrectrequest->color.alpha = color.alpha * transform.alpha;
 278   request->request_data = fillrectrequest;
 279
 280   requests->push_back(request);
 281 }
 282
 283 void
 284 DrawingContext::draw_filled_rect(const Rect& rect, const Color& color,
 285                                  int layer)
 286 {
 287   DrawingRequest* request = new(obst) DrawingRequest();
 288
 289   request->type = FILLRECT;
 290   request->pos = transform.apply(rect.p1);
 291   request->layer = layer;
 292
 293   request->drawing_effect = transform.drawing_effect;
 294   request->alpha = transform.alpha;
 295
 296   FillRectRequest* fillrectrequest = new(obst) FillRectRequest;
 297   fillrectrequest->size = Vector(rect.get_width(), rect.get_height());
 298   fillrectrequest->color = color;
 299   fillrectrequest->color.alpha = color.alpha * transform.alpha;
 300   request->request_data = fillrectrequest;
 301
 302   requests->push_back(request);
 303 }
 304
 305 void
 306 DrawingContext::get_light(const Vector& position, Color* color)
 307 {
 308   if( ambient_color.red == 1.0f && ambient_color.green == 1.0f
 309       && ambient_color.blue  == 1.0f ) {
 310     *color = Color( 1.0f, 1.0f, 1.0f);
 311     return;
 312   }
 313
 314   DrawingRequest* request = new(obst) DrawingRequest();
 315   request->type = GETLIGHT;
 316   request->pos = transform.apply(position);
 317
 318   //There is no light offscreen.
 319   if(request->pos.x >= SCREEN_WIDTH || request->pos.y >= SCREEN_HEIGHT
 320       || request->pos.x < 0 || request->pos.y < 0){
 321     *color = Color( 0, 0, 0);
 322     return;
 323   }
 324
 325   request->layer = LAYER_GUI; //make sure all get_light requests are handled last.
 326   GetLightRequest* getlightrequest = new(obst) GetLightRequest();
 327   getlightrequest->color_ptr = color;
 328   request->request_data = getlightrequest;
 329   lightmap_requests.push_back(request);
 330 }
 331
 332 void
 333 DrawingContext::get_light(const DrawingRequest& request) const
 334 {
 335   const GetLightRequest* getlightrequest
 336     = (GetLightRequest*) request.request_data;
 337
 338   float pixels[3];
 339   for( int i = 0; i<3; i++)
 340     pixels[i] = 0.0f; //set to black
 341
 342   float posX = request.pos.x * lightmap_width / SCREEN_WIDTH;
 343   float posY = screen->h - request.pos.y * lightmap_height / SCREEN_HEIGHT;
 344   glReadPixels((GLint) posX, (GLint) posY , 1, 1, GL_RGB, GL_FLOAT, pixels);
 345     *(getlightrequest->color_ptr) = Color( pixels[0], pixels[1], pixels[2]);
 346   //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]);
 347 }
 348
 349 void
 350 DrawingContext::draw_surface_part(const DrawingRequest& request) const
 351 {
 352   const SurfacePartRequest* surfacepartrequest
 353     = (SurfacePartRequest*) request.request_data;
 354
 355   surfacepartrequest->surface->draw_part(
 356       surfacepartrequest->source.x, surfacepartrequest->source.y,
 357       request.pos.x, request.pos.y,
 358       surfacepartrequest->size.x, surfacepartrequest->size.y,
 359       request.alpha, request.drawing_effect);
 360 }
 361
 362 void
 363 DrawingContext::draw_gradient(const DrawingRequest& request) const
 364 {
 365   const GradientRequest* gradientrequest
 366     = (GradientRequest*) request.request_data;
 367   const Color& top = gradientrequest->top;
 368   const Color& bottom = gradientrequest->bottom;
 369
 370   glDisable(GL_TEXTURE_2D);
 371   glBegin(GL_QUADS);
 372   glColor4f(top.red, top.green, top.blue, top.alpha);
 373   glVertex2f(0, 0);
 374   glVertex2f(SCREEN_WIDTH, 0);
 375   glColor4f(bottom.red, bottom.green, bottom.blue, bottom.alpha);
 376   glVertex2f(SCREEN_WIDTH, SCREEN_HEIGHT);
 377   glVertex2f(0, SCREEN_HEIGHT);
 378   glEnd();
 379   glEnable(GL_TEXTURE_2D);
 380 }
 381
 382 void
 383 DrawingContext::draw_text(const DrawingRequest& request) const
 384 {
 385   const TextRequest* textrequest = (TextRequest*) request.request_data;
 386
 387   textrequest->font->draw(textrequest->text, request.pos,
 388       textrequest->alignment, request.drawing_effect, request.alpha);
 389 }
 390
 391 void
 392 DrawingContext::draw_filled_rect(const DrawingRequest& request) const
 393 {
 394   const FillRectRequest* fillrectrequest
 395     = (FillRectRequest*) request.request_data;
 396
 397   float x = request.pos.x;
 398   float y = request.pos.y;
 399   float w = fillrectrequest->size.x;
 400   float h = fillrectrequest->size.y;
 401
 402   glDisable(GL_TEXTURE_2D);
 403   glColor4f(fillrectrequest->color.red, fillrectrequest->color.green,
 404             fillrectrequest->color.blue, fillrectrequest->color.alpha);
 405
 406   glBegin(GL_QUADS);
 407   glVertex2f(x, y);
 408   glVertex2f(x+w, y);
 409   glVertex2f(x+w, y+h);
 410   glVertex2f(x, y+h);
 411   glEnd();
 412   glEnable(GL_TEXTURE_2D);
 413 }
 414
 415 void
 416 DrawingContext::draw_lightmap(const DrawingRequest& request) const
 417 {
 418   const Texture* texture = reinterpret_cast<Texture*> (request.request_data);
 419
 420   // multiple the lightmap with the framebuffer
 421   glBlendFunc(GL_DST_COLOR, GL_ZERO);
 422
 423   glBindTexture(GL_TEXTURE_2D, texture->get_handle());
 424   glBegin(GL_QUADS);
 425
 426   glTexCoord2f(0, lightmap_uv_bottom);
 427   glVertex2f(0, 0);
 428
 429   glTexCoord2f(lightmap_uv_right, lightmap_uv_bottom);
 430   glVertex2f(SCREEN_WIDTH, 0);
 431
 432   glTexCoord2f(lightmap_uv_right, 0);
 433   glVertex2f(SCREEN_WIDTH, SCREEN_HEIGHT);
 434
 435   glTexCoord2f(0, 0);
 436   glVertex2f(0, SCREEN_HEIGHT);
 437
 438   glEnd();
 439
 440   glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 441 }
 442
 443 void
 444 DrawingContext::do_drawing()
 445 {
 446 #ifdef DEBUG
 447   assert(transformstack.empty());
 448   assert(target_stack.empty());
 449 #endif
 450   transformstack.clear();
 451   target_stack.clear();
 452
 453   //Use Lightmap if ambient color is not white.
 454   bool use_lightmap = ( ambient_color.red != 1.0f   || ambient_color.green != 1.0f ||
 455                         ambient_color.blue  != 1.0f );
 456
 457   // PART1: create lightmap
 458   if(use_lightmap) {
 459     glViewport(0, screen->h - lightmap_height, lightmap_width, lightmap_height);
 460     glMatrixMode(GL_PROJECTION);
 461     glLoadIdentity();
 462     glOrtho(0, SCREEN_WIDTH, SCREEN_HEIGHT, 0, -1.0, 1.0);
 463     glMatrixMode(GL_MODELVIEW);
 464     glLoadIdentity();
 465
 466     glClearColor( ambient_color.red, ambient_color.green, ambient_color.blue, 1 );
 467     glClear(GL_COLOR_BUFFER_BIT);
 468     handle_drawing_requests(lightmap_requests);
 469     lightmap_requests.clear();
 470
 471     glDisable(GL_BLEND);
 472     glBindTexture(GL_TEXTURE_2D, lightmap->get_handle());
 473     glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, screen->h - lightmap_height, lightmap_width, lightmap_height);
 474
 475     glViewport(0, 0, screen->w, screen->h);
 476     glMatrixMode(GL_PROJECTION);
 477     glLoadIdentity();
 478     glOrtho(0, SCREEN_WIDTH, SCREEN_HEIGHT, 0, -1.0, 1.0);
 479     glMatrixMode(GL_MODELVIEW);
 480     glLoadIdentity();
 481     glEnable(GL_BLEND);
 482
 483     // add a lightmap drawing request into the queue
 484     DrawingRequest* request = new(obst) DrawingRequest();
 485     request->type = LIGHTMAPREQUEST;
 486     request->layer = LAYER_HUD - 1;
 487     request->request_data = lightmap;
 488     requests->push_back(request);
 489   }
 490
 491   //glClear(GL_COLOR_BUFFER_BIT);
 492   handle_drawing_requests(drawing_requests);
 493   drawing_requests.clear();
 494   obstack_free(&obst, NULL);
 495   obstack_init(&obst);
 496   assert_gl("drawing");
 497
 498   SDL_GL_SwapBuffers();
 499 }
 500
 501 class RequestPtrCompare
 502   :  public std::binary_function<const DrawingRequest*,
 503                                  const DrawingRequest*,
 504                                  bool>
 505 {
 506 public:
 507   bool operator()(const DrawingRequest* r1, const DrawingRequest* r2) const
 508   {
 509     return *r1 < *r2;
 510   }
 511 };
 512
 513 void
 514 DrawingContext::handle_drawing_requests(DrawingRequests& requests) const
 515 {
 516   std::stable_sort(requests.begin(), requests.end(), RequestPtrCompare());
 517
 518   DrawingRequests::const_iterator i;
 519   for(i = requests.begin(); i != requests.end(); ++i) {
 520     const DrawingRequest& request = **i;
 521
 522     switch(request.type) {
 523       case SURFACE:
 524       {
 525         const Surface* surface = (const Surface*) request.request_data;
 526         if (request.angle == 0.0f &&
 527             request.color.red == 1.0f && request.color.green == 1.0f  &&
 528             request.color.blue == 1.0f &&  request.color.alpha == 1.0f) {
 529           surface->draw(request.pos.x, request.pos.y, request.alpha,
 530               request.drawing_effect);
 531         } else {
 532           surface->draw(request.pos.x, request.pos.y,
 533               request.alpha, request.angle, request.color,
 534               request.blend, request.drawing_effect);
 535         }
 536         break;
 537       }
 538       case SURFACE_PART:
 539         draw_surface_part(request);
 540         break;
 541       case GRADIENT:
 542         draw_gradient(request);
 543         break;
 544       case TEXT:
 545         draw_text(request);
 546         break;
 547       case FILLRECT:
 548         draw_filled_rect(request);
 549         break;
 550       case LIGHTMAPREQUEST:
 551         draw_lightmap(request);
 552         break;
 553       case GETLIGHT:
 554         get_light(request);
 555         break;
 556     }
 557   }
 558 }
 559
 560 void
 561 DrawingContext::push_transform()
 562 {
 563   transformstack.push_back(transform);
 564 }
 565
 566 void
 567 DrawingContext::pop_transform()
 568 {
 569   assert(!transformstack.empty());
 570
 571   transform = transformstack.back();
 572   transformstack.pop_back();
 573 }
 574
 575 void
 576 DrawingContext::set_drawing_effect(DrawingEffect effect)
 577 {
 578   transform.drawing_effect = effect;
 579 }
 580
 581 DrawingEffect
 582 DrawingContext::get_drawing_effect() const
 583 {
 584   return transform.drawing_effect;
 585 }
 586
 587 void
 588 DrawingContext::set_alpha(float alpha)
 589 {
 590   transform.alpha = alpha;
 591 }
 592
 593 float
 594 DrawingContext::get_alpha() const
 595 {
 596   return transform.alpha;
 597 }
 598
 599 void
 600 DrawingContext::push_target()
 601 {
 602   target_stack.push_back(target);
 603 }
 604
 605 void
 606 DrawingContext::pop_target()
 607 {
 608   set_target(target_stack.back());
 609   target_stack.pop_back();
 610 }
 611
 612 void
 613 DrawingContext::set_target(Target target)
 614 {
 615   this->target = target;
 616   if(target == LIGHTMAP) {
 617     requests = &lightmap_requests;
 618   } else {
 619     assert(target == NORMAL);
 620     requests = &drawing_requests;
 621   }
 622 }
 623
 624 void
 625 DrawingContext::set_ambient_color( Color new_color )
 626 {
 627   ambient_color = new_color;
 628 }