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         unsigned first_index = 0;
  35         while (m_indexes[first_index] < first_obj_id) first_index ++;
  36         unsigned last_index = first_index;
  37         while (m_indexes[last_index] < last_obj_id) last_index ++;
  38
  39         m_shader_program.Use();
  40         m_ibo.Bind();
  41         glDrawElements(GL_LINES, (last_index-first_index)*2, GL_UNSIGNED_INT, (GLvoid*)(first_index*sizeof(uint32_t)));
  42 }
  43
  44
  45 /**
  46  * Default implementation for rendering using CPU
  47  */
  48 void ObjectRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
  49 {
  50         Error("Cannot render objects of type %d on CPU", m_type);
  51         //TODO: Render a rect or something instead?
  52 }
  53
  54 /**
  55  * Prepare index buffers for both CPU and GPU rendering to receive indexes (but don't add any yet!)
  56  */
  57 void ObjectRenderer::PrepareBuffers(unsigned max_objects)
  58 {
  59         if (m_buffer_builder != NULL) // We already have a BufferBuilder
  60         {
  61                 Fatal("Has been called before, without FinaliseBuffers being called since!");
  62         }
  63         // Empty and reserve the indexes vector (for CPU rendering)
  64         m_indexes.clear();
  65         m_indexes.reserve(max_objects); //TODO: Can probably make this smaller? Or leave it out? Do we care?
  66
  67         // Initialise and resize the ibo (for GPU rendering)
  68         m_ibo.Invalidate();
  69         m_ibo.SetUsage(GraphicsBuffer::BufferUsageStaticDraw);
  70         m_ibo.SetType(GraphicsBuffer::BufferTypeIndex);
  71         m_ibo.Resize(max_objects * 2 * sizeof(uint32_t));
  72         // BufferBuilder is used to construct the ibo
  73         m_buffer_builder = new BufferBuilder<uint32_t>(m_ibo.Map(false, true, true), m_ibo.GetSize()); // new matches delete in ObjectRenderer::FinaliseBuffers
  74
  75 }
  76
  77 /**
  78  * Add object index to the buffers for CPU and GPU rendering
  79  */
  80 void ObjectRenderer::AddObjectToBuffers(unsigned index)
  81 {
  82         if (m_buffer_builder == NULL) // No BufferBuilder!
  83         {
  84                 Fatal("Called without calling PrepareBuffers");
  85         }
  86         m_buffer_builder->Add(2*index); // ibo for GPU rendering
  87         m_buffer_builder->Add(2*index+1);
  88         m_indexes.push_back(index); // std::vector of indices for CPU rendering
  89 }
  90
  91 /**
  92  * Finalise the index buffers for CPU and GPU rendering
  93  */
  94 void ObjectRenderer::FinaliseBuffers()
  95 {
  96         if (m_buffer_builder == NULL) // No BufferBuilder!
  97         {
  98                 Fatal("Called without calling PrepareBuffers");
  99         }
 100         // For GPU rendering, UnMap the ibo
 101         m_ibo.UnMap();
 102         // ... and delete the BufferBuilder used to create it
 103         delete m_buffer_builder; // delete matches new in ObjectRenderer::PrepareBuffers
 104         m_buffer_builder = NULL;
 105
 106         // Nothing is necessary for CPU rendering
 107 }
 108
 109
 110 /**
 111  * Rectangle (filled)
 112  */
 113 void RectFilledRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
 114 {
 115         for (unsigned i = 0; i < m_indexes.size(); ++i)
 116         {
 117                 if (m_indexes[i] < first_obj_id) continue;
 118                 if (m_indexes[i] >= last_obj_id) continue;
 119                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 120                 for (int64_t x = max(0L, bounds.x); x <= min(bounds.x+bounds.w, target.w-1); ++x)
 121                 {
 122                         for (int64_t y = max(0L, bounds.y); y <= min(bounds.y+bounds.h, target.h-1); ++y)
 123                         {
 124                                 int index = (x+target.w*y)*4;
 125                                 target.pixels[index+0] = 0;
 126                                 target.pixels[index+1] = 0;
 127                                 target.pixels[index+2] = 0;
 128                                 target.pixels[index+3] = 255;
 129                         }
 130                 }
 131         }
 132 }
 133
 134 /**
 135  * Rectangle (outine)
 136  */
 137 void RectOutlineRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
 138 {
 139         //Debug("Render %u outlined rectangles on CPU", m_indexes.size());
 140         for (unsigned i = 0; i < m_indexes.size(); ++i)
 141         {
 142                 if (m_indexes[i] < first_obj_id) continue;
 143                 if (m_indexes[i] >= last_obj_id) continue;
 144                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 145
 146                 // Using bresenham's lines now mainly because I want to see if they work
 147                 // top
 148                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y, bounds.x+bounds.w, bounds.y, target);
 149                 // bottom
 150                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y+bounds.h, bounds.x+bounds.w, bounds.y+bounds.h, target);
 151                 // left
 152                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y, bounds.x, bounds.y+bounds.h, target);
 153                 // right
 154                 ObjectRenderer::RenderLineOnCPU(bounds.x+bounds.w, bounds.y, bounds.x+bounds.w, bounds.y+bounds.h, target);
 155
 156                 // Diagonal for testing (from bottom left to top right)
 157                 //ObjectRenderer::RenderLineOnCPU(bounds.x,bounds.y+bounds.h, bounds.x+bounds.w, bounds.y,target, C_BLUE);
 158                 //ObjectRenderer::RenderLineOnCPU(bounds.x+bounds.w, bounds.y+bounds.h, bounds.x, bounds.y, target,C_GREEN);
 159         }
 160 }
 161
 162 /**
 163  * Circle (filled)
 164  */
 165 void CircleFilledRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
 166 {
 167         for (unsigned i = 0; i < m_indexes.size(); ++i)
 168         {
 169                 if (m_indexes[i] < first_obj_id) continue;
 170                 if (m_indexes[i] >= last_obj_id) continue;
 171                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 172                 int64_t centre_x = bounds.x + bounds.w / 2;
 173                 int64_t centre_y = bounds.y + bounds.h / 2;
 174
 175                 //Debug("Centre is %d, %d", centre_x, centre_y);
 176                 //Debug("Bounds are %d,%d,%d,%d", bounds.x, bounds.y, bounds.w, bounds.h);
 177                 //Debug("Windos is %d,%d", target.w, target.h);
 178                 for (int64_t x = max(0L, bounds.x); x <= min(bounds.x+bounds.w, target.w-1); ++x)
 179                 {
 180                         for (int64_t y = max(0L, bounds.y); y <= min(bounds.y + bounds.h, target.h-1); ++y)
 181                         {
 182                                 double dx = 2.0*(double)(x - centre_x)/(double)(bounds.w);
 183                                 double dy = 2.0*(double)(y - centre_y)/(double)(bounds.h);
 184                                 int64_t index = (x+target.w*y)*4;
 185
 186                                 if (dx*dx + dy*dy <= 1.0)
 187                                 {
 188                                         target.pixels[index+0] = 0;
 189                                         target.pixels[index+1] = 0;
 190                                         target.pixels[index+2] = 0;
 191                                         target.pixels[index+3] = 255;
 192
 193                                 }
 194                         }
 195                 }
 196         }
 197 }
 198
 199 Rect ObjectRenderer::CPURenderBounds(const Rect & bounds, const View & view, const CPURenderTarget & target)
 200 {
 201         Rect result = view.TransformToViewCoords(bounds);
 202         result.x *= Real(target.w);
 203         result.y *= Real(target.h);
 204         result.w *= Real(target.w);
 205         result.h *= Real(target.h);
 206         return result;
 207 }
 208
 209
 210 /**
 211  * Bezier curve
 212  * Not sure how to apply De'Casteljau, will just use a bunch of Bresnham lines for now.
 213  */
 214 void BezierRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
 215 {
 216         //Warn("Rendering Beziers on CPU. Things may explode.");
 217         for (unsigned i = 0; i < m_indexes.size(); ++i)
 218         {
 219                 if (m_indexes[i] < first_obj_id) continue;
 220                 if (m_indexes[i] >= last_obj_id) continue;
 221                 Rect bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 222                 PixelBounds pix_bounds(bounds);
 223
 224
 225                 Bezier control(objects.beziers[objects.data_indices[m_indexes[i]]], bounds);
 226                 //Debug("%s -> %s via %s", objects.beziers[objects.data_indices[m_indexes[i]]].Str().c_str(), control.Str().c_str(), bounds.Str().c_str());
 227                 // Draw a rectangle around the bezier for debugging the coord transforms
 228                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y, pix_bounds.x+pix_bounds.w, pix_bounds.y, target);
 229                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y+pix_bounds.h, pix_bounds.x+pix_bounds.w, pix_bounds.y+pix_bounds.h, target);
 230                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y, pix_bounds.x, pix_bounds.y+pix_bounds.h, target);
 231                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x+pix_bounds.w, pix_bounds.y, pix_bounds.x+pix_bounds.w, pix_bounds.y+pix_bounds.h, target);
 232
 233                 // Draw lines between the control points for debugging
 234                 //ObjectRenderer::RenderLineOnCPU((int64_t)control.x0, (int64_t)control.y0, (int64_t)control.x1, (int64_t)control.y1,target);
 235                 //ObjectRenderer::RenderLineOnCPU((int64_t)control.x1, (int64_t)control.y1, (int64_t)control.x2, (int64_t)control.y2,target);
 236
 237
 238
 239                 Real x[2]; Real y[2];
 240                 control.Evaluate(x[0], y[0], Real(0));
 241                 int64_t blen = max(2L, min(100L, pix_bounds.w));
 242                 Real invblen(1); invblen /= blen;
 243                 Debug("Using %li lines, inverse %f", blen, Double(invblen));
 244                 for (int64_t j = 1; j <= blen; ++j)
 245                 {
 246                         control.Evaluate(x[j % 2],y[j % 2], invblen*j);
 247                         ObjectRenderer::RenderLineOnCPU((int64_t)Double(x[0]),(int64_t)Double(y[0]), (int64_t)Double(x[1]),(int64_t)Double(y[1]), target);
 248                 }
 249
 250                 /*
 251                 Real u(0);
 252                 while (u < Real(1))
 253                 {
 254                         u += Real(1e-6);
 255                         Real x; Real y; control.Evaluate(x,y,u);
 256                         int64_t index = ((int64_t)x + (int64_t)y*target.w)*4;
 257                         if (index >= 0 && index < 4*(target.w*target.h))
 258                         {
 259                                 target.pixels[index+0] = 0;
 260                                 target.pixels[index+1] = 0;
 261                                 target.pixels[index+2] = 0;
 262                                 target.pixels[index+3] = 255;
 263                         }
 264                 }
 265                 */
 266
 267         }
 268 }
 269
 270 void BezierRenderer::PrepareBezierGPUBuffer(const Objects& objects)
 271 {
 272         m_bezier_coeffs.SetType(GraphicsBuffer::BufferTypeTexture);
 273         m_bezier_coeffs.SetUsage(GraphicsBuffer::BufferUsageDynamicDraw);
 274         m_bezier_coeffs.Resize(objects.beziers.size()*sizeof(GPUBezierCoeffs));
 275         BufferBuilder<GPUBezierCoeffs> builder(m_bezier_coeffs.Map(false, true, true), m_bezier_coeffs.GetSize());
 276
 277         for (auto bez : objects.beziers)
 278         {
 279                 GPUBezierCoeffs coeffs = {
 280                         Float(bez.x0), Float(bez.y0),
 281                         Float(bez.x1 - bez.x0), Float(bez.y1 - bez.y0),
 282                         Float(bez.x2 - bez.x0), Float(bez.y2 - bez.y0)
 283                         };
 284                 builder.Add(coeffs);
 285         }
 286         m_bezier_coeffs.UnMap();
 287         glGenTextures(1, &m_bezier_buffer_texture);
 288         glBindTexture(GL_TEXTURE_BUFFER, m_bezier_buffer_texture);
 289         glTexBuffer(GL_TEXTURE_BUFFER, GL_RG32F, m_bezier_coeffs.GetHandle());
 290
 291         m_bezier_ids.SetType(GraphicsBuffer::BufferTypeTexture);
 292         m_bezier_ids.SetUsage(GraphicsBuffer::BufferUsageDynamicDraw);
 293         m_bezier_ids.Upload(objects.data_indices.size() * sizeof(uint32_t), &objects.data_indices[0]);
 294
 295         glGenTextures(1, &m_bezier_id_buffer_texture);
 296         glActiveTexture(GL_TEXTURE1);
 297         glBindTexture(GL_TEXTURE_BUFFER, m_bezier_id_buffer_texture);
 298         glTexBuffer(GL_TEXTURE_BUFFER, GL_R32I, m_bezier_ids.GetHandle());
 299         glActiveTexture(GL_TEXTURE0);
 300 }
 301
 302 void BezierRenderer::RenderUsingGPU(unsigned first_obj_id, unsigned last_obj_id)
 303 {
 304         if (!m_shader_program.Valid())
 305                 Warn("Shader is invalid (objects are of type %d)", m_type);
 306
 307         unsigned first_index = 0;
 308         while (m_indexes[first_index] < first_obj_id) first_index ++;
 309         unsigned last_index = first_index;
 310         while (m_indexes[last_index] < last_obj_id) last_index ++;
 311
 312         m_shader_program.Use();
 313         glUniform1i(m_shader_program.GetUniformLocation("bezier_buffer_texture"), 0);
 314         glUniform1i(m_shader_program.GetUniformLocation("bezier_id_buffer_texture"), 1);
 315         m_ibo.Bind();
 316         glDrawElements(GL_LINES, (last_index-first_index)*2, GL_UNSIGNED_INT, (GLvoid*)(first_index*sizeof(uint32_t)));
 317 }
 318
 319 /**
 320  * For debug, save pixels to bitmap
 321  */
 322 void ObjectRenderer::SaveBMP(const CPURenderTarget & target, const char * filename)
 323 {
 324         SDL_Surface * surf = SDL_CreateRGBSurfaceFrom(target.pixels, target.w, target.h, 8*4, target.w*4,
 325         #if SDL_BYTEORDER == SDL_LIL_ENDIAN
 326                 0x000000ff, 0x0000ff00, 0x00ff0000, 0xff000000
 327         #else
 328                 0xff000000, 0x00ff0000, 0x0000ff00, 0x000000ff
 329         #endif //SDL_BYTEORDER
 330         );
 331         if (surf == NULL)
 332                 Fatal("SDL_CreateRGBSurfaceFrom(pixels...) failed - %s", SDL_GetError());
 333         if (SDL_SaveBMP(surf, filename) != 0)
 334                 Fatal("SDL_SaveBMP failed - %s", SDL_GetError());
 335
 336         // Cleanup
 337         SDL_FreeSurface(surf);
 338 }
 339
 340 /**
 341  * Bresenham's lines
 342  */
 343 void ObjectRenderer::RenderLineOnCPU(int64_t x0, int64_t y0, int64_t x1, int64_t y1, const CPURenderTarget & target, const Colour & colour, bool transpose)
 344 {
 345         int64_t dx = x1 - x0;
 346         int64_t dy = y1 - y0;
 347         bool neg_m = (dy*dx < 0);
 348         dy = abs(dy);
 349         dx = abs(dx);
 350
 351         // If positive slope > 1, just swap x and y
 352         if (dy > dx)
 353         {
 354                 RenderLineOnCPU(y0,x0,y1,x1,target,colour,!transpose);
 355                 return;
 356         }
 357
 358         int64_t two_dy = 2*dy;
 359         int64_t p = two_dy - dx;
 360         int64_t two_dxdy = 2*(dy-dx);
 361         int64_t x; int64_t y; int64_t x_end;
 362         int64_t width = (transpose ? target.h : target.w);
 363         int64_t height = (transpose ? target.w : target.h);
 364
 365         uint8_t rgba[4];
 366         rgba[0] = 255*colour.r;
 367         rgba[1] = 255*colour.g;
 368         rgba[2] = 255*colour.b;
 369         rgba[3] = 255*colour.a;
 370
 371         if (x0 > x1)
 372         {
 373                 x = x1;
 374                 y = y1;
 375                 x_end = x0;
 376         }
 377         else
 378         {
 379                 x = x0;
 380                 y = y0;
 381                 x_end = x1;
 382         }
 383
 384         if (x < 0)
 385         {
 386                 if (x_end < 0) return;
 387                 y = (neg_m ? y - (dy*-x)/dx : y + (dy*-x)/dx);
 388                 x = 0;
 389         }
 390
 391         if (x_end > width)
 392         {
 393                 if (x > width) return;
 394                 x_end = width-1;
 395         }
 396
 397         // TODO: Avoid extra inner conditionals
 398         do
 399         {
 400                 if (x >= 0 && x < width && y >= 0 && y < height)
 401                 {
 402                         int64_t index = (transpose ? (y + x*target.w)*4 : (x + y*target.w)*4);
 403                         for (int i = 0; i < 4; ++i)
 404                                 target.pixels[index+i] = rgba[i];
 405                 }
 406
 407                 if (p < 0)
 408                         p += two_dy;
 409                 else
 410                 {
 411                         if (neg_m) --y; else ++y;
 412                         p += two_dxdy;
 413                 }
 414         } while (++x < x_end);
 415 }
 416
 417 }