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((int64_t)0, bounds.x); x <= min(bounds.x+bounds.w, target.w-1); ++x)
 121                 {
 122                         for (int64_t y = max((int64_t)0, 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((int64_t)0, bounds.x); x <= min(bounds.x+bounds.w, target.w-1); ++x)
 179                 {
 180                         for (int64_t y = max((int64_t)0, bounds.y); y <= min(bounds.y + bounds.h, target.h-1); ++y)
 181                         {
 182                                 Real dx(2); dx *= Real(x - centre_x)/Real(bounds.w);
 183                                 Real dy(2); dy *= Real(y - centre_y)/Real(bounds.h);
 184                                 int64_t index = (x+target.w*y)*4;
 185
 186                                 if (dx*dx + dy*dy <= Real(1))
 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 Rect ObjectRenderer::CPURenderBounds(const Rect & bounds, const View & view, const CPURenderTarget & target)
 199 {
 200         Rect result = view.TransformToViewCoords(bounds);
 201         result.x *= Real(target.w);
 202         result.y *= Real(target.h);
 203         result.w *= Real(target.w);
 204         result.h *= Real(target.h);
 205         return result;
 206 }
 207
 208
 209 /**
 210  * Bezier curve
 211  * Not sure how to apply De'Casteljau, will just use a bunch of Bresnham lines for now.
 212  */
 213 void BezierRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target, unsigned first_obj_id, unsigned last_obj_id)
 214 {
 215         //Warn("Rendering Beziers on CPU. Things may explode.");
 216         for (unsigned i = 0; i < m_indexes.size(); ++i)
 217         {
 218                 if (m_indexes[i] < first_obj_id) continue;
 219                 if (m_indexes[i] >= last_obj_id) continue;
 220                 Rect bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 221                 PixelBounds pix_bounds(bounds);
 222
 223
 224                 Bezier control(objects.beziers[objects.data_indices[m_indexes[i]]], bounds);
 225                 //Debug("%s -> %s via %s", objects.beziers[objects.data_indices[m_indexes[i]]].Str().c_str(), control.Str().c_str(), bounds.Str().c_str());
 226                 // Draw a rectangle around the bezier for debugging the coord transforms
 227                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y, pix_bounds.x+pix_bounds.w, pix_bounds.y, target);
 228                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y+pix_bounds.h, pix_bounds.x+pix_bounds.w, pix_bounds.y+pix_bounds.h, target);
 229                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y, pix_bounds.x, pix_bounds.y+pix_bounds.h, target);
 230                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x+pix_bounds.w, pix_bounds.y, pix_bounds.x+pix_bounds.w, pix_bounds.y+pix_bounds.h, target);
 231
 232                 // Draw lines between the control points for debugging
 233                 //ObjectRenderer::RenderLineOnCPU((int64_t)control.x0, (int64_t)control.y0, (int64_t)control.x1, (int64_t)control.y1,target);
 234                 //ObjectRenderer::RenderLineOnCPU((int64_t)control.x1, (int64_t)control.y1, (int64_t)control.x2, (int64_t)control.y2,target);
 235
 236
 237
 238                 Real x[2]; Real y[2];
 239                 control.Evaluate(x[0], y[0], Real(0));
 240                 int64_t blen = max((int64_t)2, min((int64_t)100, pix_bounds.w));
 241                 Real invblen(1); invblen /= blen;
 242                 Debug("Using %li lines, inverse %f", blen, Double(invblen));
 243                 for (int64_t j = 1; j <= blen; ++j)
 244                 {
 245                         control.Evaluate(x[j % 2],y[j % 2], invblen*j);
 246                         ObjectRenderer::RenderLineOnCPU((int64_t)Double(x[0]),(int64_t)Double(y[0]), (int64_t)Double(x[1]),(int64_t)Double(y[1]), target);
 247                 }
 248
 249                 /*
 250                 Real u(0);
 251                 while (u < Real(1))
 252                 {
 253                         u += Real(1e-6);
 254                         Real x; Real y; control.Evaluate(x,y,u);
 255                         int64_t index = ((int64_t)x + (int64_t)y*target.w)*4;
 256                         if (index >= 0 && index < 4*(target.w*target.h))
 257                         {
 258                                 target.pixels[index+0] = 0;
 259                                 target.pixels[index+1] = 0;
 260                                 target.pixels[index+2] = 0;
 261                                 target.pixels[index+3] = 255;
 262                         }
 263                 }
 264                 */
 265
 266         }
 267 }
 268
 269 void BezierRenderer::PrepareBezierGPUBuffer(const Objects& objects)
 270 {
 271         m_bezier_coeffs.SetType(GraphicsBuffer::BufferTypeTexture);
 272         m_bezier_coeffs.SetUsage(GraphicsBuffer::BufferUsageDynamicDraw);
 273         m_bezier_coeffs.Resize(objects.beziers.size()*sizeof(GPUBezierCoeffs));
 274         BufferBuilder<GPUBezierCoeffs> builder(m_bezier_coeffs.Map(false, true, true), m_bezier_coeffs.GetSize());
 275
 276         for (auto bez = objects.beziers.begin(); bez != objects.beziers.end(); ++bez)
 277         {
 278                 GPUBezierCoeffs coeffs = {
 279                         Float(bez->x0), Float(bez->y0),
 280                         Float(bez->x1 - bez->x0), Float(bez->y1 - bez->y0),
 281                         Float(bez->x2 - bez->x0), Float(bez->y2 - bez->y0)
 282                         };
 283                 builder.Add(coeffs);
 284         }
 285         m_bezier_coeffs.UnMap();
 286         glGenTextures(1, &m_bezier_buffer_texture);
 287         glBindTexture(GL_TEXTURE_BUFFER, m_bezier_buffer_texture);
 288         glTexBuffer(GL_TEXTURE_BUFFER, GL_RG32F, m_bezier_coeffs.GetHandle());
 289
 290         m_bezier_ids.SetType(GraphicsBuffer::BufferTypeTexture);
 291         m_bezier_ids.SetUsage(GraphicsBuffer::BufferUsageDynamicDraw);
 292         m_bezier_ids.Upload(objects.data_indices.size() * sizeof(uint32_t), &objects.data_indices[0]);
 293
 294         glGenTextures(1, &m_bezier_id_buffer_texture);
 295         glActiveTexture(GL_TEXTURE1);
 296         glBindTexture(GL_TEXTURE_BUFFER, m_bezier_id_buffer_texture);
 297         glTexBuffer(GL_TEXTURE_BUFFER, GL_R32I, m_bezier_ids.GetHandle());
 298         glActiveTexture(GL_TEXTURE0);
 299 }
 300
 301 void BezierRenderer::RenderUsingGPU(unsigned first_obj_id, unsigned last_obj_id)
 302 {
 303         if (!m_shader_program.Valid())
 304                 Warn("Shader is invalid (objects are of type %d)", m_type);
 305
 306         unsigned first_index = 0;
 307         while (m_indexes[first_index] < first_obj_id) first_index ++;
 308         unsigned last_index = first_index;
 309         while (m_indexes[last_index] < last_obj_id) last_index ++;
 310
 311         m_shader_program.Use();
 312         glUniform1i(m_shader_program.GetUniformLocation("bezier_buffer_texture"), 0);
 313         glUniform1i(m_shader_program.GetUniformLocation("bezier_id_buffer_texture"), 1);
 314         m_ibo.Bind();
 315         glDrawElements(GL_LINES, (last_index-first_index)*2, GL_UNSIGNED_INT, (GLvoid*)(first_index*sizeof(uint32_t)));
 316 }
 317
 318 /**
 319  * For debug, save pixels to bitmap
 320  */
 321 void ObjectRenderer::SaveBMP(const CPURenderTarget & target, const char * filename)
 322 {
 323         SDL_Surface * surf = SDL_CreateRGBSurfaceFrom(target.pixels, target.w, target.h, 8*4, target.w*4,
 324         #if SDL_BYTEORDER == SDL_LIL_ENDIAN
 325                 0x000000ff, 0x0000ff00, 0x00ff0000, 0xff000000
 326         #else
 327                 0xff000000, 0x00ff0000, 0x0000ff00, 0x000000ff
 328         #endif //SDL_BYTEORDER
 329         );
 330         if (surf == NULL)
 331                 Fatal("SDL_CreateRGBSurfaceFrom(pixels...) failed - %s", SDL_GetError());
 332         if (SDL_SaveBMP(surf, filename) != 0)
 333                 Fatal("SDL_SaveBMP failed - %s", SDL_GetError());
 334
 335         // Cleanup
 336         SDL_FreeSurface(surf);
 337 }
 338
 339 /**
 340  * Bresenham's lines
 341  */
 342 void ObjectRenderer::RenderLineOnCPU(int64_t x0, int64_t y0, int64_t x1, int64_t y1, const CPURenderTarget & target, const Colour & colour, bool transpose)
 343 {
 344         int64_t dx = x1 - x0;
 345         int64_t dy = y1 - y0;
 346         bool neg_m = (dy*dx < 0);
 347         dy = abs(dy);
 348         dx = abs(dx);
 349
 350         // If positive slope > 1, just swap x and y
 351         if (dy > dx)
 352         {
 353                 RenderLineOnCPU(y0,x0,y1,x1,target,colour,!transpose);
 354                 return;
 355         }
 356
 357         int64_t two_dy = 2*dy;
 358         int64_t p = two_dy - dx;
 359         int64_t two_dxdy = 2*(dy-dx);
 360         int64_t x; int64_t y; int64_t x_end;
 361         int64_t width = (transpose ? target.h : target.w);
 362         int64_t height = (transpose ? target.w : target.h);
 363
 364         uint8_t rgba[4];
 365         rgba[0] = 255*colour.r;
 366         rgba[1] = 255*colour.g;
 367         rgba[2] = 255*colour.b;
 368         rgba[3] = 255*colour.a;
 369
 370         if (x0 > x1)
 371         {
 372                 x = x1;
 373                 y = y1;
 374                 x_end = x0;
 375         }
 376         else
 377         {
 378                 x = x0;
 379                 y = y0;
 380                 x_end = x1;
 381         }
 382
 383         if (x < 0)
 384         {
 385                 if (x_end < 0) return;
 386                 y = (neg_m ? y - (dy*-x)/dx : y + (dy*-x)/dx);
 387                 x = 0;
 388         }
 389
 390         if (x_end > width)
 391         {
 392                 if (x > width) return;
 393                 x_end = width-1;
 394         }
 395
 396         // TODO: Avoid extra inner conditionals
 397         do
 398         {
 399                 if (x >= 0 && x < width && y >= 0 && y < height)
 400                 {
 401                         int64_t index = (transpose ? (y + x*target.w)*4 : (x + y*target.w)*4);
 402                         for (int i = 0; i < 4; ++i)
 403                                 target.pixels[index+i] = rgba[i];
 404                 }
 405
 406                 if (p < 0)
 407                         p += two_dy;
 408                 else
 409                 {
 410                         if (neg_m) --y; else ++y;
 411                         p += two_dxdy;
 412                 }
 413         } while (++x < x_end);
 414 }
 415
 416 }