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