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         if (vert_glsl_file != NULL && frag_glsl_file != NULL && geom_glsl_file != NULL)
  28         {
  29                 m_shader_program.InitialiseShaders(vert_glsl_file, frag_glsl_file, geom_glsl_file);
  30                 m_shader_program.Use();
  31                 glUniform4f(m_shader_program.GetUniformLocation("colour"), 0,0,0,1); //TODO: Allow different colours
  32         }
  33 }
  34
  35 /**
  36  * Render using GPU
  37  */
  38 void ObjectRenderer::RenderUsingGPU(unsigned first_obj_id, unsigned last_obj_id)
  39 {
  40         // If we don't have anything to render, return.
  41         if (first_obj_id == last_obj_id) return;
  42         // If there are no objects of this type, return.
  43         if (m_indexes.empty()) return;
  44         unsigned first_index = 0;
  45         while (m_indexes.size() > first_index && m_indexes[first_index] < first_obj_id) first_index ++;
  46         unsigned last_index = first_index;
  47         while (m_indexes.size() > last_index && m_indexes[last_index] < last_obj_id) last_index ++;
  48
  49         m_shader_program.Use();
  50         m_ibo.Bind();
  51         glDrawElements(GL_LINES, (last_index-first_index)*2, GL_UNSIGNED_INT, (GLvoid*)(2*first_index*sizeof(uint32_t)));
  52 }
  53
  54
  55 /**
  56  * Default implementation for rendering using CPU
  57  */
  58 void ObjectRenderer::RenderUsingCPU(Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
  59 {
  60         Error("Cannot render objects of type %d on CPU", m_type);
  61         //TODO: Render a rect or something instead?
  62 }
  63
  64 /**
  65  * Prepare index buffers for both CPU and GPU rendering to receive indexes (but don't add any yet!)
  66  */
  67 void ObjectRenderer::PrepareBuffers(unsigned max_objects)
  68 {
  69         if (m_buffer_builder != NULL) // We already have a BufferBuilder
  70         {
  71                 Fatal("Has been called before, without FinaliseBuffers being called since!");
  72         }
  73         // Empty and reserve the indexes vector (for CPU rendering)
  74         m_indexes.clear();
  75         m_indexes.reserve(max_objects); //TODO: Can probably make this smaller? Or leave it out? Do we care?
  76
  77         // Initialise and resize the ibo (for GPU rendering)
  78         m_ibo.Invalidate();
  79         m_ibo.SetUsage(GraphicsBuffer::BufferUsageStaticDraw);
  80         m_ibo.SetType(GraphicsBuffer::BufferTypeIndex);
  81         m_ibo.Resize(max_objects * 2 * sizeof(uint32_t));
  82         // BufferBuilder is used to construct the ibo
  83         m_buffer_builder = new BufferBuilder<uint32_t>(m_ibo.Map(false, true, true), m_ibo.GetSize()); // new matches delete in ObjectRenderer::FinaliseBuffers
  84
  85 }
  86
  87 /**
  88  * Add object index to the buffers for CPU and GPU rendering
  89  */
  90 void ObjectRenderer::AddObjectToBuffers(unsigned index)
  91 {
  92         if (m_buffer_builder == NULL) // No BufferBuilder!
  93         {
  94                 Fatal("Called without calling PrepareBuffers");
  95         }
  96         m_buffer_builder->Add(2*index); // ibo for GPU rendering
  97         m_buffer_builder->Add(2*index+1);
  98         m_indexes.push_back(index); // std::vector of indices for CPU rendering
  99 }
 100
 101 /**
 102  * Finalise the index buffers for CPU and GPU rendering
 103  */
 104 void ObjectRenderer::FinaliseBuffers()
 105 {
 106         if (m_buffer_builder == NULL) // No BufferBuilder!
 107         {
 108                 Fatal("Called without calling PrepareBuffers");
 109         }
 110         // For GPU rendering, UnMap the ibo
 111         m_ibo.UnMap();
 112         // ... and delete the BufferBuilder used to create it
 113         delete m_buffer_builder; // delete matches new in ObjectRenderer::PrepareBuffers
 114         m_buffer_builder = NULL;
 115
 116         // Nothing is necessary for CPU rendering
 117 }
 118
 119
 120 /**
 121  * Rectangle (filled)
 122  */
 123 void RectFilledRenderer::RenderUsingCPU(Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
 124 {
 125         for (unsigned i = 0; i < m_indexes.size(); ++i)
 126         {
 127                 if (m_indexes[i] < first_obj_id) continue;
 128                 if (m_indexes[i] >= last_obj_id) continue;
 129                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 130                 FloodFillOnCPU(bounds.x+1, bounds.y+1, bounds, target, Colour(0,0,0,1));
 131                 /*
 132                 for (int64_t x = max((int64_t)0, bounds.x); x <= min(bounds.x+bounds.w, target.w-1); ++x)
 133                 {
 134                         for (int64_t y = max((int64_t)0, bounds.y); y <= min(bounds.y+bounds.h, target.h-1); ++y)
 135                         {
 136                                 int index = (x+target.w*y)*4;
 137                                 target.pixels[index+0] = 0;
 138                                 target.pixels[index+1] = 0;
 139                                 target.pixels[index+2] = 0;
 140                                 target.pixels[index+3] = 255;
 141                         }
 142                 }
 143                 */
 144         }
 145 }
 146
 147 /**
 148  * Rectangle (outine)
 149  */
 150 void RectOutlineRenderer::RenderUsingCPU(Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
 151 {
 152         //Debug("Render %u outlined rectangles on CPU", m_indexes.size());
 153         for (unsigned i = 0; i < m_indexes.size(); ++i)
 154         {
 155                 if (m_indexes[i] < first_obj_id) continue;
 156                 if (m_indexes[i] >= last_obj_id) continue;
 157                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 158
 159                 // Using bresenham's lines now mainly because I want to see if they work
 160                 // top
 161                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y, bounds.x+bounds.w, bounds.y, target);
 162                 // bottom
 163                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y+bounds.h, bounds.x+bounds.w, bounds.y+bounds.h, target);
 164                 // left
 165                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y, bounds.x, bounds.y+bounds.h, target);
 166                 // right
 167                 ObjectRenderer::RenderLineOnCPU(bounds.x+bounds.w, bounds.y, bounds.x+bounds.w, bounds.y+bounds.h, target);
 168
 169                 // Diagonal for testing (from bottom left to top right)
 170                 //ObjectRenderer::RenderLineOnCPU(bounds.x,bounds.y+bounds.h, bounds.x+bounds.w, bounds.y,target, C_BLUE);
 171                 //ObjectRenderer::RenderLineOnCPU(bounds.x+bounds.w, bounds.y+bounds.h, bounds.x, bounds.y, target,C_GREEN);
 172         }
 173 }
 174
 175 /**
 176  * Circle (filled)
 177  */
 178 void CircleFilledRenderer::RenderUsingCPU(Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
 179 {
 180         for (unsigned i = 0; i < m_indexes.size(); ++i)
 181         {
 182                 if (m_indexes[i] < first_obj_id) continue;
 183                 if (m_indexes[i] >= last_obj_id) continue;
 184                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 185                 int64_t centre_x = bounds.x + bounds.w / 2;
 186                 int64_t centre_y = bounds.y + bounds.h / 2;
 187
 188                 //Debug("Centre is %d, %d", centre_x, centre_y);
 189                 //Debug("Bounds are %d,%d,%d,%d", bounds.x, bounds.y, bounds.w, bounds.h);
 190                 //Debug("Windos is %d,%d", target.w, target.h);
 191                 for (int64_t x = max((int64_t)0, bounds.x); x <= min(bounds.x+bounds.w, target.w-1); ++x)
 192                 {
 193                         for (int64_t y = max((int64_t)0, bounds.y); y <= min(bounds.y + bounds.h, target.h-1); ++y)
 194                         {
 195                                 Real dx(2); dx *= Real(x - centre_x)/Real(bounds.w);
 196                                 Real dy(2); dy *= Real(y - centre_y)/Real(bounds.h);
 197                                 int64_t index = (x+target.w*y)*4;
 198
 199                                 if (dx*dx + dy*dy <= Real(1))
 200                                 {
 201                                         target.pixels[index+0] = 0;
 202                                         target.pixels[index+1] = 0;
 203                                         target.pixels[index+2] = 0;
 204                                         target.pixels[index+3] = 255;
 205                                 }
 206                         }
 207                 }
 208         }
 209 }
 210
 211 Rect ObjectRenderer::CPURenderBounds(const Rect & bounds, const View & view, const CPURenderTarget & target)
 212 {
 213         Rect result = view.TransformToViewCoords(bounds);
 214         result.x *= Real(target.w);
 215         result.y *= Real(target.h);
 216         result.w *= Real(target.w);
 217         result.h *= Real(target.h);
 218         return result;
 219 }
 220
 221 ObjectRenderer::PixelPoint ObjectRenderer::CPUPointLocation(const Vec2 & point, const View & view, const CPURenderTarget & target)
 222 {
 223         // hack...
 224         Rect result = view.TransformToViewCoords(Rect(point.x, point.y,1,1));
 225         int64_t x = Int64(result.x)*target.w;
 226         int64_t y = Int64(result.y)*target.h;
 227         return PixelPoint(x,y);
 228 }
 229
 230
 231 void BezierRenderer::RenderBezierOnCPU(const Bezier & relative, const Rect & bounds, const View & view, const CPURenderTarget & target, const Colour & c)
 232 {
 233         //const Rect & bounds = objects.bounds[i];
 234         PixelBounds pix_bounds(CPURenderBounds(bounds,view,target));
 235         //Bezier control(objects.beziers[objects.data_indices[i]].ToAbsolute(bounds),CPURenderBounds(Rect(0,0,1,1), view, target));
 236         Bezier control(relative.ToAbsolute(bounds), Rect(0,0,target.w, target.h));
 237
 238         if (view.ShowingBezierBounds())
 239         {
 240                 ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y, pix_bounds.x+pix_bounds.w, pix_bounds.y, target, Colour(255,0,0,0));
 241                 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(0,255,0,0));
 242                 ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y, pix_bounds.x, pix_bounds.y+pix_bounds.h, target, Colour(255,0,0,0));
 243                 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(0,255,0,0));
 244         }
 245
 246         int64_t blen =  min((int64_t)50,pix_bounds.w);//min(max(2U, (unsigned)Int64(Real(target.w)/view.GetBounds().w)),
 247                         //min((unsigned)(pix_bounds.w+pix_bounds.h)/4 + 1, 100U));
 248
 249                 // DeCasteljau Divide the Bezier
 250         #ifdef BEZIER_CPU_DECASTELJAU
 251         queue<Bezier> divisions;
 252         divisions.push(control);
 253         while(divisions.size() < (uint64_t)(blen))
 254         {
 255                 Bezier & current = divisions.front();
 256                 //if (current.GetType() == Bezier::LINE)
 257                 //{
 258                 //      --blen;
 259                 //      continue;
 260                 //}
 261                 divisions.push(current.DeCasteljauSubdivideRight(Real(1)/Real(2)));
 262                 divisions.push(current.DeCasteljauSubdivideLeft(Real(1)/Real(2)));
 263                 divisions.pop();
 264         }
 265         while (divisions.size() > 0)
 266         {
 267                 Bezier & current = divisions.front();
 268                 RenderLineOnCPU(Int64(current.x0), Int64(current.y0), Int64(current.x3), Int64(current.y3), target, c);
 269                 divisions.pop();
 270         }
 271         #else
 272                 Real invblen(1); invblen /= Real(blen);
 273
 274                 Real t(invblen);
 275                 Vec2 v0;
 276                 Vec2 v1;
 277                 control.Evaluate(v0.x, v0.y, 0);
 278                 for (int64_t j = 1; j <= blen; ++j)
 279                 {
 280                         control.Evaluate(v1.x, v1.y, t);
 281                         RenderLineOnCPU(v0.x, v0.y, v1.x, v1.y, target);
 282                         t += invblen;
 283                         v0 = v1;
 284                 }
 285         #endif //BEZIER_CPU_DECASTELJAU
 286 }
 287
 288 /**
 289  * Bezier curve
 290  * Not sure how to apply De'Casteljau, will just use a bunch of Bresnham lines for now.
 291  */
 292 void BezierRenderer::RenderUsingCPU(Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
 293 {
 294         #ifdef TRANSFORM_BEZIERS_TO_PATH
 295                 return;
 296         #endif
 297         if (view.PerformingShading())
 298                 return;
 299
 300         //Warn("Rendering Beziers on CPU. Things may explode.");
 301         for (unsigned i = 0; i < m_indexes.size(); ++i)
 302         {
 303                 if (m_indexes[i] < first_obj_id) continue;
 304                 if (m_indexes[i] >= last_obj_id) continue;
 305                 Colour c(0,0,0,255);
 306                 if (view.ShowingBezierType())
 307                 {
 308                         switch (objects.beziers[objects.data_indices[m_indexes[i]]].GetType())
 309                         {
 310                                 case Bezier::LINE:
 311                                         break;
 312                                 case Bezier::QUADRATIC:
 313                                         c.b = 255;
 314                                         break;
 315                                 case Bezier::SERPENTINE:
 316                                         c.r = 255;
 317                                         break;
 318                                 case Bezier::CUSP:
 319                                         c.g = 255;
 320                                         break;
 321                                 case Bezier::LOOP:
 322                                         c.r = 128;
 323                                         c.b = 128;
 324                                         break;
 325                                 default:
 326                                         c.r = 128;
 327                                         c.g = 128;
 328                                         break;
 329                         }
 330                 }
 331                 Rect bounds = view.TransformToViewCoords(objects.bounds[m_indexes[i]]);
 332                 Bezier & bez = objects.beziers[objects.data_indices[m_indexes[i]]];
 333                 RenderBezierOnCPU(bez, bounds, view, target, c);
 334         }
 335 }
 336
 337 void BezierRenderer::PrepareBezierGPUBuffer(Objects & objects)
 338 {
 339         m_bezier_coeffs.SetType(GraphicsBuffer::BufferTypeTexture);
 340         m_bezier_coeffs.SetUsage(GraphicsBuffer::BufferUsageDynamicDraw);
 341         m_bezier_coeffs.Resize(objects.beziers.size()*sizeof(GPUBezierCoeffs));
 342         BufferBuilder<GPUBezierCoeffs> builder(m_bezier_coeffs.Map(false, true, true), m_bezier_coeffs.GetSize());
 343
 344
 345         for (unsigned i = 0; i < objects.beziers.size(); ++i)
 346         {
 347                 const Bezier & bez = objects.beziers[i];
 348                 GPUBezierCoeffs coeffs = {
 349                         Float(bez.x0), Float(bez.y0),
 350                         Float(bez.x1), Float(bez.y1),
 351                         Float(bez.x2), Float(bez.y2),
 352                         Float(bez.x3), Float(bez.y3)
 353                         };
 354                 builder.Add(coeffs);
 355         }
 356
 357         m_bezier_coeffs.UnMap();
 358         glGenTextures(1, &m_bezier_buffer_texture);
 359         glBindTexture(GL_TEXTURE_BUFFER, m_bezier_buffer_texture);
 360         glTexBuffer(GL_TEXTURE_BUFFER, GL_RG32F, m_bezier_coeffs.GetHandle());
 361
 362         m_bezier_ids.SetType(GraphicsBuffer::BufferTypeTexture);
 363         m_bezier_ids.SetUsage(GraphicsBuffer::BufferUsageDynamicDraw);
 364         m_bezier_ids.Upload(objects.data_indices.size() * sizeof(uint32_t), &objects.data_indices[0]);
 365
 366         glGenTextures(1, &m_bezier_id_buffer_texture);
 367         glActiveTexture(GL_TEXTURE1);
 368         glBindTexture(GL_TEXTURE_BUFFER, m_bezier_id_buffer_texture);
 369         glTexBuffer(GL_TEXTURE_BUFFER, GL_R32I, m_bezier_ids.GetHandle());
 370         glActiveTexture(GL_TEXTURE0);
 371 }
 372
 373 void BezierRenderer::RenderUsingGPU(unsigned first_obj_id, unsigned last_obj_id)
 374 {
 375
 376         if (!m_shader_program.Valid())
 377                 Warn("Shader is invalid (objects are of type %d)", m_type);
 378
 379         // If we don't have anything to render, return.
 380         if (first_obj_id == last_obj_id) return;
 381         // If there are no objects of this type, return.
 382         if (m_indexes.empty()) return;
 383
 384         unsigned first_index = 0;
 385         while (m_indexes.size() > first_index && m_indexes[first_index] < first_obj_id) first_index ++;
 386         unsigned last_index = first_index;
 387         while (m_indexes.size() > last_index && m_indexes[last_index] < last_obj_id) last_index ++;
 388
 389         m_shader_program.Use();
 390         glUniform1i(m_shader_program.GetUniformLocation("bezier_buffer_texture"), 0);
 391         glUniform1i(m_shader_program.GetUniformLocation("bezier_id_buffer_texture"), 1);
 392         m_ibo.Bind();
 393
 394         // To antialias the line... causes SIGFPE because why would anything make sense
 395         //glEnable(GL_BLEND);
 396         //glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 397         //glEnable(GL_LINE_SMOOTH);
 398         //glHint(GL_LINE_SMOOTH_HINT, GL_NICEST);
 399         glDrawElements(GL_LINES, (last_index-first_index)*2, GL_UNSIGNED_INT, (GLvoid*)(2*first_index*sizeof(uint32_t)));
 400 }
 401
 402
 403
 404 /**
 405  * Render Path (shading)
 406  */
 407 void PathRenderer::RenderUsingCPU(Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
 408 {
 409
 410
 411         for (unsigned i = 0; i < m_indexes.size(); ++i)
 412         {
 413                 if (m_indexes[i] < first_obj_id) continue;
 414                 if (m_indexes[i] >= last_obj_id) continue;
 415
 416
 417
 418                 Path & path = objects.paths[objects.data_indices[m_indexes[i]]];
 419                 Rect bounds(CPURenderBounds(path.GetBounds(objects), view, target));
 420                 PixelBounds pix_bounds(bounds);
 421
 422                 if (view.ShowingFillPoints())
 423                 {
 424
 425                         PixelPoint start(CPUPointLocation((path.m_top+path.m_left+path.m_right+path.m_bottom)/4, view, target));
 426                         for (unsigned f = 0; f < path.m_fill_points.size(); ++f)
 427                         {
 428                                 PixelPoint end(CPUPointLocation(path.m_fill_points[f], view, target));
 429                                 RenderLineOnCPU(start.first, start.second, end.first, end.second, target, Colour(0,0,255,0));
 430                         }
 431                 }
 432
 433                 #ifndef TRANSFORM_BEZIERS_TO_PATH
 434                 if (!view.PerformingShading())
 435                         continue;
 436                 for (unsigned b = path.m_start; b <= path.m_end; ++b)
 437                 {
 438                         Rect bbounds = view.TransformToViewCoords(objects.bounds[b]);
 439                         Bezier & bez = objects.beziers[objects.data_indices[b]];
 440                         BezierRenderer::RenderBezierOnCPU(bez,bbounds,view,target,path.m_stroke);
 441                 }
 442                 #else
 443                 // Outlines still get drawn if using TRANSFORM_BEZIERS_TO_PATH
 444                 for (unsigned b = path.m_start; b <= path.m_end; ++b)
 445                 {
 446                         Colour stroke = (view.PerformingShading()) ? path.m_stroke : Colour(0,0,0,255);
 447                         // bezier's bounds are relative to this object's bounds, convert back to view bounds
 448                         Rect bbounds = objects.bounds[b];
 449                         bbounds.x *= objects.bounds[m_indexes[i]].w;
 450                         bbounds.x += objects.bounds[m_indexes[i]].x;
 451                         bbounds.y *= objects.bounds[m_indexes[i]].h;
 452                         bbounds.y += objects.bounds[m_indexes[i]].y;
 453                         bbounds.w *= objects.bounds[m_indexes[i]].w;
 454                         bbounds.h *= objects.bounds[m_indexes[i]].h;
 455                         bbounds = view.TransformToViewCoords(bbounds);
 456                         //Debug("Bounds: %s", objects.bounds[m_indexes[i]].Str().c_str());
 457                         //Debug("Relative Bez Bounds: %s", objects.bounds[b].Str().c_str());
 458                         //Debug("Bez Bounds: %s", bbounds.Str().c_str());
 459
 460                         Bezier & bez = objects.beziers[objects.data_indices[b]];
 461
 462                         BezierRenderer::RenderBezierOnCPU(bez,bbounds,view,target, stroke);
 463                 }
 464                 if (!view.PerformingShading())
 465                         continue;
 466                 #endif
 467
 468
 469                 if (pix_bounds.w*pix_bounds.h > 100)
 470                 {
 471                         vector<Vec2> & fill_points = path.FillPoints(objects, view);
 472                         Debug("High resolution; use fill points %u,%u", pix_bounds.w, pix_bounds.h);
 473                         for (unsigned f = 0; f < fill_points.size(); ++f)
 474                         {
 475                                 PixelPoint fill_point(CPUPointLocation(fill_points[f], view, target));
 476
 477                                 FloodFillOnCPU(fill_point.first, fill_point.second, pix_bounds, target, path.m_fill, path.m_stroke);
 478                         }
 479                 }
 480                 else
 481                 {
 482                         Debug("Low resolution; use brute force %u,%u",pix_bounds.w, pix_bounds.h);
 483                         int64_t y_min = max((int64_t)0, pix_bounds.y);
 484                         int64_t y_max = min(pix_bounds.y+pix_bounds.h, target.h);
 485                         int64_t x_min = max((int64_t)0, pix_bounds.x);
 486                         int64_t x_max = min(pix_bounds.x+pix_bounds.w, target.w);
 487                         for (int64_t y = y_min; y < y_max; ++y)
 488                         {
 489                                 for (int64_t x = x_min; x < x_max; ++x)
 490                                 {
 491                                         Rect pb(path.SolveBounds(objects));
 492                                         Vec2 pt(pb.x + (Real(x-pix_bounds.x)/Real(pix_bounds.w))*pb.w,
 493                                                         pb.y + (Real(y-pix_bounds.y)/Real(pix_bounds.h))*pb.h);
 494                                         if (path.PointInside(objects, pt))
 495                                         {
 496                                                 FloodFillOnCPU(x, y, pix_bounds, target, path.m_fill, path.m_stroke);
 497                                         }
 498                                 }
 499                         }
 500                 }
 501         }
 502 }
 503
 504
 505
 506
 507 /**
 508  * For debug, save pixels to bitmap
 509  */
 510 void ObjectRenderer::SaveBMP(const CPURenderTarget & target, const char * filename)
 511 {
 512         SDL_Surface * surf = SDL_CreateRGBSurfaceFrom(target.pixels, target.w, target.h, 8*4, target.w*4,
 513         #if SDL_BYTEORDER == SDL_LIL_ENDIAN
 514                 0x000000ff, 0x0000ff00, 0x00ff0000, 0xff000000
 515         #else
 516                 0xff000000, 0x00ff0000, 0x0000ff00, 0x000000ff
 517         #endif //SDL_BYTEORDER
 518         );
 519         if (surf == NULL)
 520                 Fatal("SDL_CreateRGBSurfaceFrom(pixels...) failed - %s", SDL_GetError());
 521         if (SDL_SaveBMP(surf, filename) != 0)
 522                 Fatal("SDL_SaveBMP failed - %s", SDL_GetError());
 523
 524         // Cleanup
 525         SDL_FreeSurface(surf);
 526 }
 527
 528
 529
 530
 531 /**
 532  * Bresenham's lines
 533  */
 534 void ObjectRenderer::RenderLineOnCPU(int64_t x0, int64_t y0, int64_t x1, int64_t y1, const CPURenderTarget & target, const Colour & colour, bool transpose)
 535 {
 536         int64_t dx = x1 - x0;
 537         int64_t dy = y1 - y0;
 538         bool neg_m = (dy*dx < 0);
 539         dy = abs(dy);
 540         dx = abs(dx);
 541
 542         // If positive slope > 1, just swap x and y
 543         if (dy > dx)
 544         {
 545                 RenderLineOnCPU(y0,x0,y1,x1,target,colour,!transpose);
 546                 return;
 547         }
 548
 549         int64_t two_dy = 2*dy;
 550         int64_t p = two_dy - dx;
 551         int64_t two_dxdy = 2*(dy-dx);
 552         int64_t x; int64_t y; int64_t x_end;
 553         int64_t width = (transpose ? target.h : target.w);
 554         int64_t height = (transpose ? target.w : target.h);
 555
 556         if (x0 > x1)
 557         {
 558                 x = x1;
 559                 y = y1;
 560                 x_end = x0;
 561         }
 562         else
 563         {
 564                 x = x0;
 565                 y = y0;
 566                 x_end = x1;
 567         }
 568
 569         if (x < 0)
 570         {
 571                 if (x_end < 0) return;
 572                 y = (neg_m ? y - (dy*-x)/dx : y + (dy*-x)/dx);
 573                 x = 0;
 574         }
 575
 576         if (x_end > width)
 577         {
 578                 if (x > width) return;
 579                 x_end = width-1;
 580         }
 581
 582         // TODO: Avoid extra inner conditionals
 583         do
 584         {
 585                 if (x >= 0 && x < width && y >= 0 && y < height)
 586                 {
 587                         int64_t index = (transpose ? (y + x*target.w)*4 : (x + y*target.w)*4);
 588                         target.pixels[index+0] = colour.r;
 589                         target.pixels[index+1] = colour.g;
 590                         target.pixels[index+2] = colour.b;
 591                         target.pixels[index+3] = colour.a;
 592                 }
 593                 if (p < 0)
 594                         p += two_dy;
 595                 else
 596                 {
 597                         if (neg_m) --y; else ++y;
 598                         p += two_dxdy;
 599                 }
 600         } while (++x <= x_end);
 601 }
 602
 603
 604 void ObjectRenderer::FloodFillOnCPU(int64_t x, int64_t y, const PixelBounds & bounds, const CPURenderTarget & target, const Colour & fill, const Colour & stroke)
 605 {
 606         // HACK to prevent overflooding (when the fill points for a path round to the pixel outside the boundary)
 607         // (I totally just made that term up...)
 608         Colour c = GetColour(target, x+1, y);
 609         if (c == fill || c == stroke)
 610                 return;
 611         c = GetColour(target, x-1, y);
 612         if (c == fill || c == stroke)
 613                 return;
 614         c = GetColour(target, x, y+1);
 615         if (c == fill || c == stroke)
 616                 return;
 617         c = GetColour(target, x, y-1);
 618         if (c == fill || c == stroke)
 619                 return;
 620
 621         // The hack works but now we get underflooding, or, "droughts".
 622
 623
 624         queue<PixelPoint > traverse;
 625         traverse.push(PixelPoint(x,y));
 626         // now with 100% less stack overflows!
 627         while (traverse.size() > 0)
 628         {
 629                 PixelPoint cur(traverse.front());
 630                 traverse.pop();
 631                 if (cur.first < 0 || cur.first < bounds.x || cur.first >= bounds.x+bounds.w || cur.first >= target.w ||
 632                         cur.second < 0 || cur.second < bounds.y || cur.second >= bounds.y+bounds.h || cur.second >= target.h)
 633                         continue;
 634                 c = GetColour(target, cur.first, cur.second);
 635                 if (c == fill || c == stroke)
 636                         continue;
 637
 638                 SetColour(target, cur.first, cur.second, fill);
 639
 640                 //Debug("c is {%u,%u,%u,%u} fill is {%u,%u,%u,%u}, stroke is {%u,%u,%u,%u}",
 641                 //      c.r,c.g,c.b,c.a, fill.r,fill.g,fill.b,fill.a, stroke.r,stroke.g,stroke.b,stroke.a);
 642
 643                 traverse.push(PixelPoint(cur.first+1, cur.second));
 644                 traverse.push(PixelPoint(cur.first-1, cur.second));
 645                 traverse.push(PixelPoint(cur.first, cur.second-1));
 646                 traverse.push(PixelPoint(cur.first, cur.second+1));
 647         }
 648 }
 649
 650 ObjectRenderer::PixelBounds::PixelBounds(const Rect & bounds)
 651 {
 652         x = Int64(Double(bounds.x));
 653         y = Int64(Double(bounds.y));
 654         w = Int64(Double(bounds.w));
 655         h = Int64(Double(bounds.h));
 656 }
 657
 658 }