src/objectrenderer.cpp

   1 /**
   2  * @file objectrenderer.cpp
   3  * @brief Implements ObjectRenderer and derived classes
   4  */
   5
   6 #include "objectrenderer.h"
   7 #include "view.h"
   8 #include <vector>
   9 #include <queue>
  10 #include <stack>
  11
  12 using namespace std;
  13
  14 namespace IPDF
  15 {
  16
  17 /**
  18  * ObjectRenderer constructor
  19  * Note we cannot compile the shaders in the ShaderProgram constructor
  20  *  because the Screen class needs to initialise GL first and it has a
  21  *      ShaderProgram member
  22  */
  23 ObjectRenderer::ObjectRenderer(const ObjectType & type,
  24                 const char * vert_glsl_file, const char * frag_glsl_file, const char * geom_glsl_file)
  25                 : m_type(type), m_shader_program(), m_indexes(), m_buffer_builder(NULL)
  26 {
  27         m_shader_program.InitialiseShaders(vert_glsl_file, frag_glsl_file, geom_glsl_file);
  28         m_shader_program.Use();
  29         glUniform4f(m_shader_program.GetUniformLocation("colour"), 0,0,0,1); //TODO: Allow different colours
  30 }
  31
  32 /**
  33  * Render using GPU
  34  */
  35 void ObjectRenderer::RenderUsingGPU(unsigned first_obj_id, unsigned last_obj_id)
  36 {
  37         // If we don't have anything to render, return.
  38         if (first_obj_id == last_obj_id) return;
  39         // If there are no objects of this type, return.
  40         if (m_indexes.empty()) return;
  41         unsigned first_index = 0;
  42         while (m_indexes.size() > first_index && m_indexes[first_index] < first_obj_id) first_index ++;
  43         unsigned last_index = first_index;
  44         while (m_indexes.size() > last_index && m_indexes[last_index] < last_obj_id) last_index ++;
  45
  46         m_shader_program.Use();
  47         m_ibo.Bind();
  48         glDrawElements(GL_LINES, (last_index-first_index)*2, GL_UNSIGNED_INT, (GLvoid*)(2*first_index*sizeof(uint32_t)));
  49 }
  50
  51
  52 /**
  53  * Default implementation for rendering using CPU
  54  */
  55 void ObjectRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
  56 {
  57         Error("Cannot render objects of type %d on CPU", m_type);
  58         //TODO: Render a rect or something instead?
  59 }
  60
  61 /**
  62  * Prepare index buffers for both CPU and GPU rendering to receive indexes (but don't add any yet!)
  63  */
  64 void ObjectRenderer::PrepareBuffers(unsigned max_objects)
  65 {
  66         if (m_buffer_builder != NULL) // We already have a BufferBuilder
  67         {
  68                 Fatal("Has been called before, without FinaliseBuffers being called since!");
  69         }
  70         // Empty and reserve the indexes vector (for CPU rendering)
  71         m_indexes.clear();
  72         m_indexes.reserve(max_objects); //TODO: Can probably make this smaller? Or leave it out? Do we care?
  73
  74         // Initialise and resize the ibo (for GPU rendering)
  75         m_ibo.Invalidate();
  76         m_ibo.SetUsage(GraphicsBuffer::BufferUsageStaticDraw);
  77         m_ibo.SetType(GraphicsBuffer::BufferTypeIndex);
  78         m_ibo.Resize(max_objects * 2 * sizeof(uint32_t));
  79         // BufferBuilder is used to construct the ibo
  80         m_buffer_builder = new BufferBuilder<uint32_t>(m_ibo.Map(false, true, true), m_ibo.GetSize()); // new matches delete in ObjectRenderer::FinaliseBuffers
  81
  82 }
  83
  84 /**
  85  * Add object index to the buffers for CPU and GPU rendering
  86  */
  87 void ObjectRenderer::AddObjectToBuffers(unsigned index)
  88 {
  89         if (m_buffer_builder == NULL) // No BufferBuilder!
  90         {
  91                 Fatal("Called without calling PrepareBuffers");
  92         }
  93         m_buffer_builder->Add(2*index); // ibo for GPU rendering
  94         m_buffer_builder->Add(2*index+1);
  95         m_indexes.push_back(index); // std::vector of indices for CPU rendering
  96 }
  97
  98 /**
  99  * Finalise the index buffers for CPU and GPU rendering
 100  */
 101 void ObjectRenderer::FinaliseBuffers()
 102 {
 103         if (m_buffer_builder == NULL) // No BufferBuilder!
 104         {
 105                 Fatal("Called without calling PrepareBuffers");
 106         }
 107         // For GPU rendering, UnMap the ibo
 108         m_ibo.UnMap();
 109         // ... and delete the BufferBuilder used to create it
 110         delete m_buffer_builder; // delete matches new in ObjectRenderer::PrepareBuffers
 111         m_buffer_builder = NULL;
 112
 113         // Nothing is necessary for CPU rendering
 114 }
 115
 116
 117 /**
 118  * Rectangle (filled)
 119  */
 120 void RectFilledRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
 121 {
 122         for (unsigned i = 0; i < m_indexes.size(); ++i)
 123         {
 124                 if (m_indexes[i] < first_obj_id) continue;
 125                 if (m_indexes[i] >= last_obj_id) continue;
 126                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 127                 FloodFillOnCPU(bounds.x+1, bounds.y+1, bounds, target, Colour(0,0,0,1));
 128                 /*
 129                 for (int64_t x = max((int64_t)0, bounds.x); x <= min(bounds.x+bounds.w, target.w-1); ++x)
 130                 {
 131                         for (int64_t y = max((int64_t)0, bounds.y); y <= min(bounds.y+bounds.h, target.h-1); ++y)
 132                         {
 133                                 int index = (x+target.w*y)*4;
 134                                 target.pixels[index+0] = 0;
 135                                 target.pixels[index+1] = 0;
 136                                 target.pixels[index+2] = 0;
 137                                 target.pixels[index+3] = 255;
 138                         }
 139                 }
 140                 */
 141         }
 142 }
 143
 144 /**
 145  * Rectangle (outine)
 146  */
 147 void RectOutlineRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
 148 {
 149         //Debug("Render %u outlined rectangles on CPU", m_indexes.size());
 150         for (unsigned i = 0; i < m_indexes.size(); ++i)
 151         {
 152                 if (m_indexes[i] < first_obj_id) continue;
 153                 if (m_indexes[i] >= last_obj_id) continue;
 154                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 155
 156                 // Using bresenham's lines now mainly because I want to see if they work
 157                 // top
 158                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y, bounds.x+bounds.w, bounds.y, target);
 159                 // bottom
 160                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y+bounds.h, bounds.x+bounds.w, bounds.y+bounds.h, target);
 161                 // left
 162                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y, bounds.x, bounds.y+bounds.h, target);
 163                 // right
 164                 ObjectRenderer::RenderLineOnCPU(bounds.x+bounds.w, bounds.y, bounds.x+bounds.w, bounds.y+bounds.h, target);
 165
 166                 // Diagonal for testing (from bottom left to top right)
 167                 //ObjectRenderer::RenderLineOnCPU(bounds.x,bounds.y+bounds.h, bounds.x+bounds.w, bounds.y,target, C_BLUE);
 168                 //ObjectRenderer::RenderLineOnCPU(bounds.x+bounds.w, bounds.y+bounds.h, bounds.x, bounds.y, target,C_GREEN);
 169         }
 170 }
 171
 172 /**
 173  * Circle (filled)
 174  */
 175 void CircleFilledRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
 176 {
 177         for (unsigned i = 0; i < m_indexes.size(); ++i)
 178         {
 179                 if (m_indexes[i] < first_obj_id) continue;
 180                 if (m_indexes[i] >= last_obj_id) continue;
 181                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 182                 int64_t centre_x = bounds.x + bounds.w / 2;
 183                 int64_t centre_y = bounds.y + bounds.h / 2;
 184
 185                 //Debug("Centre is %d, %d", centre_x, centre_y);
 186                 //Debug("Bounds are %d,%d,%d,%d", bounds.x, bounds.y, bounds.w, bounds.h);
 187                 //Debug("Windos is %d,%d", target.w, target.h);
 188                 for (int64_t x = max((int64_t)0, bounds.x); x <= min(bounds.x+bounds.w, target.w-1); ++x)
 189                 {
 190                         for (int64_t y = max((int64_t)0, bounds.y); y <= min(bounds.y + bounds.h, target.h-1); ++y)
 191                         {
 192                                 Real dx(2); dx *= Real(x - centre_x)/Real(bounds.w);
 193                                 Real dy(2); dy *= Real(y - centre_y)/Real(bounds.h);
 194                                 int64_t index = (x+target.w*y)*4;
 195
 196                                 if (dx*dx + dy*dy <= Real(1))
 197                                 {
 198                                         target.pixels[index+0] = 0;
 199                                         target.pixels[index+1] = 0;
 200                                         target.pixels[index+2] = 0;
 201                                         target.pixels[index+3] = 255;
 202                                 }
 203                         }
 204                 }
 205         }
 206 }
 207
 208 Rect ObjectRenderer::CPURenderBounds(const Rect & bounds, const View & view, const CPURenderTarget & target)
 209 {
 210         Rect result = view.TransformToViewCoords(bounds);
 211         result.x *= Real(target.w);
 212         result.y *= Real(target.h);
 213         result.w *= Real(target.w);
 214         result.h *= Real(target.h);
 215         return result;
 216 }
 217
 218 ObjectRenderer::PixelPoint ObjectRenderer::CPUPointLocation(const Vec2 & point, const View & view, const CPURenderTarget & target)
 219 {
 220         // hack...
 221         Rect result = view.TransformToViewCoords(Rect(point.x, point.y,1,1));
 222         int64_t x = result.x*target.w;
 223         int64_t y = result.y*target.h;
 224         return PixelPoint(x,y);
 225 }
 226
 227
 228 /**
 229  * Bezier curve
 230  * Not sure how to apply De'Casteljau, will just use a bunch of Bresnham lines for now.
 231  */
 232 void BezierRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
 233 {
 234         //Warn("Rendering Beziers on CPU. Things may explode.");
 235         for (unsigned i = 0; i < m_indexes.size(); ++i)
 236         {
 237                 if (m_indexes[i] < first_obj_id) continue;
 238                 if (m_indexes[i] >= last_obj_id) continue;
 239                 const Rect & bounds = objects.bounds[m_indexes[i]];
 240                 PixelBounds pix_bounds(CPURenderBounds(bounds,view,target));
 241
 242                 Bezier control(objects.beziers[objects.data_indices[m_indexes[i]]].ToAbsolute(bounds),CPURenderBounds(Rect(0,0,1,1), view, target));
 243                 //Debug("%s -> %s via %s", objects.beziers[objects.data_indices[m_indexes[i]]].Str().c_str(), control.Str().c_str(), bounds.Str().c_str());
 244                 // Draw a rectangle around the bezier for debugging the bounds rectangle calculations
 245                 if (view.ShowingObjectBounds())
 246                 {
 247                         ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y, pix_bounds.x+pix_bounds.w, pix_bounds.y, target, Colour(1,0,0,1));
 248                         ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y+pix_bounds.h, pix_bounds.x+pix_bounds.w, pix_bounds.y+pix_bounds.h, target, Colour(0,1,0,1));
 249                         ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y, pix_bounds.x, pix_bounds.y+pix_bounds.h, target, Colour(1,0,0,1));
 250                         ObjectRenderer::RenderLineOnCPU(pix_bounds.x+pix_bounds.w, pix_bounds.y, pix_bounds.x+pix_bounds.w, pix_bounds.y+pix_bounds.h, target, Colour(0,1,0,1));
 251                 }
 252                 // Draw lines between the control points for debugging
 253                 //ObjectRenderer::RenderLineOnCPU((int64_t)control.x0, (int64_t)control.y0, (int64_t)control.x1, (int64_t)control.y1,target);
 254                 //ObjectRenderer::RenderLineOnCPU((int64_t)control.x1, (int64_t)control.y1, (int64_t)control.x2, (int64_t)control.y2,target);
 255
 256
 257
 258
 259                 unsigned blen = min(max(2U, (unsigned)(target.w/view.GetBounds().w)), min((unsigned)(pix_bounds.w+pix_bounds.h)/4 + 1, 100U));
 260
 261                 // DeCasteljau Divide the Bezier
 262                 queue<Bezier> divisions;
 263                 divisions.push(control);
 264                 while(divisions.size() < blen)
 265                 {
 266                         Bezier & current = divisions.front();
 267                         if (current.GetType() == Bezier::LINE)
 268                         {
 269                                 --blen;
 270                                 continue;
 271                         }
 272                         divisions.push(current.DeCasteljauSubdivideRight(Real(1)/Real(2)));
 273                         divisions.push(current.DeCasteljauSubdivideLeft(Real(1)/Real(2)));
 274                         divisions.pop();
 275
 276                         //Debug("divisions %u", divisions.size());
 277                 }
 278                 while (divisions.size() > 0)
 279                 {
 280                         Bezier & current = divisions.front();
 281                         RenderLineOnCPU(current.x0, current.y0, current.x3, current.y3, target, Colour(0,0,0,!view.PerformingShading()));
 282                         divisions.pop();
 283                 }
 284
 285                 /* Draw the Bezier by sampling
 286                 Real invblen(1); invblen /= blen;
 287                 Real t(invblen);
 288                 Vec2 v0;
 289                 Vec2 v1;
 290                 control.Evaluate(v0.x, v0.y, 0);
 291                 for (int64_t j = 1; j <= blen; ++j)
 292                 {
 293                         control.Evaluate(v1.x, v1.y, t);
 294
 295                         ObjectRenderer::RenderLineOnCPU(v0.x, v0.y, v1.x, v1.y, target, Colour(0,0,0,!view.PerformingShading()));
 296                         //ObjectRenderer::SetColour(target, x[0], y[0], Colour(1,0,0,1));
 297                         //ObjectRenderer::SetColour(target, x[1], y[1], Colour(0,0,1,1));
 298                         t += invblen;
 299                         v0 = v1;
 300                 }
 301                 */
 302         }
 303 }
 304
 305 void BezierRenderer::PrepareBezierGPUBuffer(const Objects& objects)
 306 {
 307         m_bezier_coeffs.SetType(GraphicsBuffer::BufferTypeTexture);
 308         m_bezier_coeffs.SetUsage(GraphicsBuffer::BufferUsageDynamicDraw);
 309         m_bezier_coeffs.Resize(objects.beziers.size()*sizeof(GPUBezierCoeffs));
 310         BufferBuilder<GPUBezierCoeffs> builder(m_bezier_coeffs.Map(false, true, true), m_bezier_coeffs.GetSize());
 311
 312
 313         for (unsigned i = 0; i < objects.beziers.size(); ++i)
 314         {
 315                 const Bezier & bez = objects.beziers[i];
 316
 317                 GPUBezierCoeffs coeffs = {
 318                         Float(bez.x0), Float(bez.y0),
 319                         Float(bez.x1), Float(bez.y1),
 320                         Float(bez.x2), Float(bez.y2),
 321                         Float(bez.x3), Float(bez.y3)
 322                         };
 323                 builder.Add(coeffs);
 324         }
 325         m_bezier_coeffs.UnMap();
 326         glGenTextures(1, &m_bezier_buffer_texture);
 327         glBindTexture(GL_TEXTURE_BUFFER, m_bezier_buffer_texture);
 328         glTexBuffer(GL_TEXTURE_BUFFER, GL_RG32F, m_bezier_coeffs.GetHandle());
 329
 330         m_bezier_ids.SetType(GraphicsBuffer::BufferTypeTexture);
 331         m_bezier_ids.SetUsage(GraphicsBuffer::BufferUsageDynamicDraw);
 332         m_bezier_ids.Upload(objects.data_indices.size() * sizeof(uint32_t), &objects.data_indices[0]);
 333
 334         glGenTextures(1, &m_bezier_id_buffer_texture);
 335         glActiveTexture(GL_TEXTURE1);
 336         glBindTexture(GL_TEXTURE_BUFFER, m_bezier_id_buffer_texture);
 337         glTexBuffer(GL_TEXTURE_BUFFER, GL_R32I, m_bezier_ids.GetHandle());
 338         glActiveTexture(GL_TEXTURE0);
 339 }
 340
 341 void BezierRenderer::RenderUsingGPU(unsigned first_obj_id, unsigned last_obj_id)
 342 {
 343         if (!m_shader_program.Valid())
 344                 Warn("Shader is invalid (objects are of type %d)", m_type);
 345
 346         // If we don't have anything to render, return.
 347         if (first_obj_id == last_obj_id) return;
 348         // If there are no objects of this type, return.
 349         if (m_indexes.empty()) return;
 350
 351         unsigned first_index = 0;
 352         while (m_indexes.size() > first_index && m_indexes[first_index] < first_obj_id) first_index ++;
 353         unsigned last_index = first_index;
 354         while (m_indexes.size() > last_index && m_indexes[last_index] < last_obj_id) last_index ++;
 355
 356         m_shader_program.Use();
 357         glUniform1i(m_shader_program.GetUniformLocation("bezier_buffer_texture"), 0);
 358         glUniform1i(m_shader_program.GetUniformLocation("bezier_id_buffer_texture"), 1);
 359         m_ibo.Bind();
 360         glDrawElements(GL_LINES, (last_index-first_index)*2, GL_UNSIGNED_INT, (GLvoid*)(2*first_index*sizeof(uint32_t)));
 361 }
 362
 363
 364
 365 /**
 366  * Render Path (shading)
 367  */
 368 void PathRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
 369 {
 370         if (!view.ShowingObjectBounds() && !view.PerformingShading())
 371                 return;
 372
 373         for (unsigned i = 0; i < m_indexes.size(); ++i)
 374         {
 375                 if (m_indexes[i] < first_obj_id) continue;
 376                 if (m_indexes[i] >= last_obj_id) continue;
 377
 378
 379                 Rect bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 380                 PixelBounds pix_bounds(bounds);
 381                 const Path & path = objects.paths[objects.data_indices[m_indexes[i]]];
 382                 if (path.m_fill.a == 0 || !view.PerformingShading())
 383                         continue;
 384
 385                 for (unsigned f = 0; f < path.m_fill_points.size(); ++f)
 386                 {
 387                         PixelPoint fill_point(CPUPointLocation(path.m_fill_points[f], view, target));
 388                         FloodFillOnCPU(fill_point.first, fill_point.second, pix_bounds, target, path.m_fill);
 389                 }
 390
 391                 /*if (true)//(view.ShowingObjectBounds())
 392                 {
 393
 394                         PixelPoint start(CPUPointLocation((path.m_top+path.m_left+path.m_right+path.m_bottom)/4, view, target));
 395                         for (unsigned f = 0; f < path.m_fill_points.size(); ++f)
 396                         {
 397                                 PixelPoint end(CPUPointLocation(path.m_fill_points[f], view, target));
 398                                 RenderLineOnCPU(start.first, start.second, end.first, end.second, target, Colour(0,0,1,1));
 399                         }
 400                 }
 401                 */
 402
 403         }
 404 }
 405
 406 /**
 407  * For debug, save pixels to bitmap
 408  */
 409 void ObjectRenderer::SaveBMP(const CPURenderTarget & target, const char * filename)
 410 {
 411         SDL_Surface * surf = SDL_CreateRGBSurfaceFrom(target.pixels, target.w, target.h, 8*4, target.w*4,
 412         #if SDL_BYTEORDER == SDL_LIL_ENDIAN
 413                 0x000000ff, 0x0000ff00, 0x00ff0000, 0xff000000
 414         #else
 415                 0xff000000, 0x00ff0000, 0x0000ff00, 0x000000ff
 416         #endif //SDL_BYTEORDER
 417         );
 418         if (surf == NULL)
 419                 Fatal("SDL_CreateRGBSurfaceFrom(pixels...) failed - %s", SDL_GetError());
 420         if (SDL_SaveBMP(surf, filename) != 0)
 421                 Fatal("SDL_SaveBMP failed - %s", SDL_GetError());
 422
 423         // Cleanup
 424         SDL_FreeSurface(surf);
 425 }
 426
 427 /**
 428  * Bresenham's lines
 429  */
 430 void ObjectRenderer::RenderLineOnCPU(int64_t x0, int64_t y0, int64_t x1, int64_t y1, const CPURenderTarget & target, const Colour & colour, bool transpose)
 431 {
 432         int64_t dx = x1 - x0;
 433         int64_t dy = y1 - y0;
 434         bool neg_m = (dy*dx < 0);
 435         dy = abs(dy);
 436         dx = abs(dx);
 437
 438         // If positive slope > 1, just swap x and y
 439         if (dy > dx)
 440         {
 441                 RenderLineOnCPU(y0,x0,y1,x1,target,colour,!transpose);
 442                 return;
 443         }
 444
 445         int64_t two_dy = 2*dy;
 446         int64_t p = two_dy - dx;
 447         int64_t two_dxdy = 2*(dy-dx);
 448         int64_t x; int64_t y; int64_t x_end;
 449         int64_t width = (transpose ? target.h : target.w);
 450         int64_t height = (transpose ? target.w : target.h);
 451
 452         uint8_t rgba[4];
 453         rgba[0] = 255*colour.r;
 454         rgba[1] = 255*colour.g;
 455         rgba[2] = 255*colour.b;
 456         rgba[3] = 255*colour.a;
 457
 458         if (x0 > x1)
 459         {
 460                 x = x1;
 461                 y = y1;
 462                 x_end = x0;
 463         }
 464         else
 465         {
 466                 x = x0;
 467                 y = y0;
 468                 x_end = x1;
 469         }
 470
 471         if (x < 0)
 472         {
 473                 if (x_end < 0) return;
 474                 y = (neg_m ? y - (dy*-x)/dx : y + (dy*-x)/dx);
 475                 x = 0;
 476         }
 477
 478         if (x_end > width)
 479         {
 480                 if (x > width) return;
 481                 x_end = width-1;
 482         }
 483
 484         // TODO: Avoid extra inner conditionals
 485         do
 486         {
 487                 if (x >= 0 && x < width && y >= 0 && y < height)
 488                 {
 489                         int64_t index = (transpose ? (y + x*target.w)*4 : (x + y*target.w)*4);
 490                         for (int i = 0; i < 4; ++i)
 491                                 target.pixels[index+i] = rgba[i];
 492                 }
 493                 if (p < 0)
 494                         p += two_dy;
 495                 else
 496                 {
 497                         if (neg_m) --y; else ++y;
 498                         p += two_dxdy;
 499                 }
 500         } while (++x <= x_end);
 501 }
 502
 503 void ObjectRenderer::FloodFillOnCPU(int64_t x, int64_t y, const PixelBounds & bounds, const CPURenderTarget & target, const Colour & fill)
 504 {
 505         if (fill == Colour(1,1,1,1))
 506                 return;
 507         queue<PixelPoint > traverse;
 508         traverse.push(PixelPoint(x,y));
 509         // now with 100% less stack overflows!
 510         while (traverse.size() > 0)
 511         {
 512                 PixelPoint cur(traverse.front());
 513                 traverse.pop();
 514                 if (cur.first < 0 || cur.first < bounds.x || cur.first >= bounds.x+bounds.w || cur.first >= target.w ||
 515                         cur.second < 0 || cur.second < bounds.y || cur.second >= bounds.y+bounds.h || cur.second >= target.h)
 516                         continue;
 517                 if (GetColour(target, cur.first, cur.second) != Colour(1,1,1,1))
 518                         continue;
 519                 SetColour(target, cur.first, cur.second, fill);
 520
 521
 522                 traverse.push(PixelPoint(cur.first+1, cur.second));
 523                 traverse.push(PixelPoint(cur.first-1, cur.second));
 524                 traverse.push(PixelPoint(cur.first, cur.second-1));
 525                 traverse.push(PixelPoint(cur.first, cur.second+1));
 526         }
 527 }
 528
 529 }