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 constructor because the Screen class needs to initialise GL and it has a ShaderProgram member
  17  */
  18 ObjectRenderer::ObjectRenderer(const ObjectType & type,
  19                 const char * vert_glsl_file, const char * frag_glsl_file, const char * geom_glsl_file)
  20                 : m_type(type), m_shader_program(), m_indexes(), m_buffer_builder(NULL)
  21 {
  22         m_shader_program.InitialiseShaders(vert_glsl_file, frag_glsl_file, geom_glsl_file);
  23         m_shader_program.Use();
  24         glUniform4f(m_shader_program.GetUniformLocation("colour"), 0,0,0,1); //TODO: Allow different colours
  25 }
  26
  27 /**
  28  * Render using GPU
  29  */
  30 void ObjectRenderer::RenderUsingGPU()
  31 {
  32         if (!m_shader_program.Valid())
  33                 Warn("Shader is invalid (objects are of type %d)", m_type);
  34         m_shader_program.Use();
  35         m_ibo.Bind();
  36         glDrawElements(GL_LINES, m_indexes.size()*2, GL_UNSIGNED_INT, 0);
  37 }
  38
  39
  40 /**
  41  * Default implementation for rendering using CPU
  42  */
  43 void ObjectRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target)
  44 {
  45         Error("Cannot render objects of type %d on CPU", m_type);
  46         //TODO: Render a rect or something instead?
  47 }
  48
  49 /**
  50  * Prepare index buffers for both CPU and GPU rendering to receive indexes (but don't add any yet!)
  51  */
  52 void ObjectRenderer::PrepareBuffers(unsigned max_objects)
  53 {
  54         if (m_buffer_builder != NULL) // We already have a BufferBuilder
  55         {
  56                 Fatal("Has been called before, without FinaliseBuffers being called since!");
  57         }
  58         // Empty and reserve the indexes vector (for CPU rendering)
  59         m_indexes.clear();
  60         m_indexes.reserve(max_objects); //TODO: Can probably make this smaller? Or leave it out? Do we care?
  61
  62         // Initialise and resize the ibo (for GPU rendering)
  63         m_ibo.Invalidate();
  64         m_ibo.SetUsage(GraphicsBuffer::BufferUsageStaticDraw);
  65         m_ibo.SetType(GraphicsBuffer::BufferTypeIndex);
  66         m_ibo.Resize(max_objects * 2 * sizeof(uint32_t));
  67         // BufferBuilder is used to construct the ibo
  68         m_buffer_builder = new BufferBuilder<uint32_t>(m_ibo.Map(false, true, true), m_ibo.GetSize()); // new matches delete in ObjectRenderer::FinaliseBuffers
  69
  70 }
  71
  72 /**
  73  * Add object index to the buffers for CPU and GPU rendering
  74  */
  75 void ObjectRenderer::AddObjectToBuffers(unsigned index)
  76 {
  77         if (m_buffer_builder == NULL) // No BufferBuilder!
  78         {
  79                 Fatal("Called without calling PrepareBuffers");
  80         }
  81         m_buffer_builder->Add(2*index); // ibo for GPU rendering
  82         m_buffer_builder->Add(2*index+1);
  83         m_indexes.push_back(index); // std::vector of indices for CPU rendering
  84 }
  85
  86 /**
  87  * Finalise the index buffers for CPU and GPU rendering
  88  */
  89 void ObjectRenderer::FinaliseBuffers()
  90 {
  91         if (m_buffer_builder == NULL) // No BufferBuilder!
  92         {
  93                 Fatal("Called without calling PrepareBuffers");
  94         }
  95         // For GPU rendering, UnMap the ibo
  96         m_ibo.UnMap();
  97         // ... and delete the BufferBuilder used to create it
  98         delete m_buffer_builder; // delete matches new in ObjectRenderer::PrepareBuffers
  99         m_buffer_builder = NULL;
 100
 101         // Nothing is necessary for CPU rendering
 102 }
 103
 104
 105 /**
 106  * Rectangle (filled)
 107  */
 108 void RectFilledRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target)
 109 {
 110         for (unsigned i = 0; i < m_indexes.size(); ++i)
 111         {
 112                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 113                 for (int64_t x = max(0L, bounds.x); x <= min(bounds.x+bounds.w, target.w-1); ++x)
 114                 {
 115                         for (int64_t y = max(0L, bounds.y); y <= min(bounds.y+bounds.h, target.h-1); ++y)
 116                         {
 117                                 int index = (x+target.w*y)*4;
 118                                 target.pixels[index+0] = 0;
 119                                 target.pixels[index+1] = 0;
 120                                 target.pixels[index+2] = 0;
 121                                 target.pixels[index+3] = 255;
 122                         }
 123                 }
 124         }
 125 }
 126
 127 /**
 128  * Rectangle (outine)
 129  */
 130 void RectOutlineRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target)
 131 {
 132         //Debug("Render %u outlined rectangles on CPU", m_indexes.size());
 133         for (unsigned i = 0; i < m_indexes.size(); ++i)
 134         {
 135                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 136
 137                 // Using bresenham's lines now mainly because I want to see if they work
 138                 // top
 139                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y, bounds.x+bounds.w, bounds.y, target);
 140                 // bottom
 141                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y+bounds.h, bounds.x+bounds.w, bounds.y+bounds.h, target);
 142                 // left
 143                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y, bounds.x, bounds.y+bounds.h, target);
 144                 // right
 145                 ObjectRenderer::RenderLineOnCPU(bounds.x+bounds.w, bounds.y, bounds.x+bounds.w, bounds.y+bounds.h, target);
 146
 147                 // Diagonal for testing (from bottom left to top right)
 148                 //ObjectRenderer::RenderLineOnCPU(bounds.x,bounds.y+bounds.h, bounds.x+bounds.w, bounds.y,target, C_BLUE);
 149                 //ObjectRenderer::RenderLineOnCPU(bounds.x+bounds.w, bounds.y+bounds.h, bounds.x, bounds.y, target,C_GREEN);
 150         }
 151 }
 152
 153 /**
 154  * Circle (filled)
 155  */
 156 void CircleFilledRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target)
 157 {
 158         for (unsigned i = 0; i < m_indexes.size(); ++i)
 159         {
 160                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 161                 int64_t centre_x = bounds.x + bounds.w / 2;
 162                 int64_t centre_y = bounds.y + bounds.h / 2;
 163
 164                 //Debug("Centre is %d, %d", centre_x, centre_y);
 165                 //Debug("Bounds are %d,%d,%d,%d", bounds.x, bounds.y, bounds.w, bounds.h);
 166                 //Debug("Windos is %d,%d", target.w, target.h);
 167                 for (int64_t x = max(0L, bounds.x); x <= min(bounds.x+bounds.w, target.w-1); ++x)
 168                 {
 169                         for (int64_t y = max(0L, bounds.y); y <= min(bounds.y + bounds.h, target.h-1); ++y)
 170                         {
 171                                 double dx = 2.0*(double)(x - centre_x)/(double)(bounds.w);
 172                                 double dy = 2.0*(double)(y - centre_y)/(double)(bounds.h);
 173                                 int64_t index = (x+target.w*y)*4;
 174
 175                                 if (dx*dx + dy*dy <= 1.0)
 176                                 {
 177                                         target.pixels[index+0] = 0;
 178                                         target.pixels[index+1] = 0;
 179                                         target.pixels[index+2] = 0;
 180                                         target.pixels[index+3] = 255;
 181
 182                                 }
 183                         }
 184                 }
 185         }
 186 }
 187
 188 Rect ObjectRenderer::CPURenderBounds(const Rect & bounds, const View & view, const CPURenderTarget & target)
 189 {
 190         Rect result = view.TransformToViewCoords(bounds);
 191         result.x *= Real(target.w);
 192         result.y *= Real(target.h);
 193         result.w *= Real(target.w);
 194         result.h *= Real(target.h);
 195         return result;
 196 }
 197
 198
 199 /**
 200  * Bezier curve
 201  * Not sure how to apply De'Casteljau, will just use a bunch of Bresnham lines for now.
 202  */
 203 void BezierRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target)
 204 {
 205         //Warn("Rendering Beziers on CPU. Things may explode.");
 206         for (unsigned i = 0; i < m_indexes.size(); ++i)
 207         {
 208                 Rect bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 209                 PixelBounds pix_bounds(bounds);
 210
 211
 212                 Bezier control(objects.beziers[objects.data_indices[m_indexes[i]]], bounds);
 213                 //Debug("%s -> %s via %s", objects.beziers[objects.data_indices[m_indexes[i]]].Str().c_str(), control.Str().c_str(), bounds.Str().c_str());
 214                 // Draw a rectangle around the bezier for debugging the coord transforms
 215                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y, pix_bounds.x+pix_bounds.w, pix_bounds.y, target);
 216                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y+pix_bounds.h, pix_bounds.x+pix_bounds.w, pix_bounds.y+pix_bounds.h, target);
 217                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y, pix_bounds.x, pix_bounds.y+pix_bounds.h, target);
 218                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x+pix_bounds.w, pix_bounds.y, pix_bounds.x+pix_bounds.w, pix_bounds.y+pix_bounds.h, target);
 219
 220                 // Draw lines between the control points for debugging
 221                 //ObjectRenderer::RenderLineOnCPU((int64_t)control.x0, (int64_t)control.y0, (int64_t)control.x1, (int64_t)control.y1,target);
 222                 //ObjectRenderer::RenderLineOnCPU((int64_t)control.x1, (int64_t)control.y1, (int64_t)control.x2, (int64_t)control.y2,target);
 223
 224
 225
 226                 Real x[2]; Real y[2];
 227                 control.Evaluate(x[0], y[0], Real(0));
 228                 for (unsigned j = 1; j <= 100; ++j)
 229                 {
 230                         control.Evaluate(x[j % 2],y[j % 2], Real(0.01)*j);
 231                         ObjectRenderer::RenderLineOnCPU((int64_t)Double(x[0]),(int64_t)Double(y[0]), (int64_t)Double(x[1]),(int64_t)Double(y[1]), target);
 232                 }
 233
 234                 /*
 235                 Real u(0);
 236                 while (u < Real(1))
 237                 {
 238                         u += Real(1e-6);
 239                         Real x; Real y; control.Evaluate(x,y,u);
 240                         int64_t index = ((int64_t)x + (int64_t)y*target.w)*4;
 241                         if (index >= 0 && index < 4*(target.w*target.h))
 242                         {
 243                                 target.pixels[index+0] = 0;
 244                                 target.pixels[index+1] = 0;
 245                                 target.pixels[index+2] = 0;
 246                                 target.pixels[index+3] = 255;
 247                         }
 248                 }
 249                 */
 250
 251         }
 252 }
 253
 254 void BezierRenderer::PrepareBezierGPUBuffer(const Objects& objects)
 255 {
 256         m_bezier_coeffs.SetType(GraphicsBuffer::BufferTypeTexture);
 257         m_bezier_coeffs.SetUsage(GraphicsBuffer::BufferUsageDynamicDraw);
 258         m_bezier_coeffs.Resize(objects.beziers.size()*sizeof(GPUBezierCoeffs));
 259         BufferBuilder<GPUBezierCoeffs> builder(m_bezier_coeffs.Map(false, true, true), m_bezier_coeffs.GetSize());
 260
 261         for (auto bez : objects.beziers)
 262         {
 263                 GPUBezierCoeffs coeffs = {
 264                         Float(bez.x0), Float(bez.y0),
 265                         Float(bez.x1 - bez.x0), Float(bez.y1 - bez.y0),
 266                         Float(bez.x2 - bez.x0), Float(bez.y2 - bez.y0)
 267                         };
 268                 builder.Add(coeffs);
 269         }
 270         m_bezier_coeffs.UnMap();
 271         glGenTextures(1, &m_bezier_buffer_texture);
 272         glBindTexture(GL_TEXTURE_BUFFER, m_bezier_buffer_texture);
 273         glTexBuffer(GL_TEXTURE_BUFFER, GL_RG32F, m_bezier_coeffs.GetHandle());
 274
 275         m_bezier_ids.SetType(GraphicsBuffer::BufferTypeTexture);
 276         m_bezier_ids.SetUsage(GraphicsBuffer::BufferUsageDynamicDraw);
 277         m_bezier_ids.Upload(objects.data_indices.size() * sizeof(uint32_t), &objects.data_indices[0]);
 278
 279         glGenTextures(1, &m_bezier_id_buffer_texture);
 280         glActiveTexture(GL_TEXTURE1);
 281         glBindTexture(GL_TEXTURE_BUFFER, m_bezier_id_buffer_texture);
 282         glTexBuffer(GL_TEXTURE_BUFFER, GL_R32I, m_bezier_ids.GetHandle());
 283         glActiveTexture(GL_TEXTURE0);
 284 }
 285
 286 void BezierRenderer::RenderUsingGPU()
 287 {
 288         if (!m_shader_program.Valid())
 289                 Warn("Shader is invalid (objects are of type %d)", m_type);
 290         m_shader_program.Use();
 291         glUniform1i(m_shader_program.GetUniformLocation("bezier_buffer_texture"), 0);
 292         glUniform1i(m_shader_program.GetUniformLocation("bezier_id_buffer_texture"), 1);
 293         m_ibo.Bind();
 294         glDrawElements(GL_LINES, m_indexes.size()*2, GL_UNSIGNED_INT, 0);
 295 }
 296
 297 /**
 298  * For debug, save pixels to bitmap
 299  */
 300 void ObjectRenderer::SaveBMP(const CPURenderTarget & target, const char * filename)
 301 {
 302         SDL_Surface * surf = SDL_CreateRGBSurfaceFrom(target.pixels, target.w, target.h, 8*4, target.w*4,
 303         #if SDL_BYTEORDER == SDL_LIL_ENDIAN
 304                 0x000000ff, 0x0000ff00, 0x00ff0000, 0xff000000
 305         #else
 306                 0xff000000, 0x00ff0000, 0x0000ff00, 0x000000ff
 307         #endif //SDL_BYTEORDER
 308         );
 309         if (surf == NULL)
 310                 Fatal("SDL_CreateRGBSurfaceFrom(pixels...) failed - %s", SDL_GetError());
 311         if (SDL_SaveBMP(surf, filename) != 0)
 312                 Fatal("SDL_SaveBMP failed - %s", SDL_GetError());
 313
 314         // Cleanup
 315         SDL_FreeSurface(surf);
 316 }
 317
 318 /**
 319  * Bresenham's lines
 320  */
 321 void ObjectRenderer::RenderLineOnCPU(int64_t x0, int64_t y0, int64_t x1, int64_t y1, const CPURenderTarget & target, const Colour & colour, bool transpose)
 322 {
 323         int64_t dx = x1 - x0;
 324         int64_t dy = y1 - y0;
 325         bool neg_m = (dy*dx < 0);
 326         dy = abs(dy);
 327         dx = abs(dx);
 328
 329         // If positive slope > 1, just swap x and y
 330         if (dy > dx)
 331         {
 332                 RenderLineOnCPU(y0,x0,y1,x1,target,colour,!transpose);
 333                 return;
 334         }
 335
 336         int64_t two_dy = 2*dy;
 337         int64_t p = two_dy - dx;
 338         int64_t two_dxdy = 2*(dy-dx);
 339         int64_t x; int64_t y; int64_t x_end;
 340         int64_t width = (transpose ? target.h : target.w);
 341         int64_t height = (transpose ? target.w : target.h);
 342
 343         uint8_t rgba[4];
 344         rgba[0] = 255*colour.r;
 345         rgba[1] = 255*colour.g;
 346         rgba[2] = 255*colour.b;
 347         rgba[3] = 255*colour.a;
 348
 349         if (x0 > x1)
 350         {
 351                 x = x1;
 352                 y = y1;
 353                 x_end = x0;
 354         }
 355         else
 356         {
 357                 x = x0;
 358                 y = y0;
 359                 x_end = x1;
 360         }
 361
 362         if (x < 0)
 363         {
 364                 if (x_end < 0) return;
 365                 y = (neg_m ? y - (dy*-x)/dx : y + (dy*-x)/dx);
 366                 x = 0;
 367         }
 368
 369         if (x_end > width)
 370         {
 371                 if (x > width) return;
 372                 x_end = width-1;
 373         }
 374
 375         // TODO: Avoid extra inner conditionals
 376         do
 377         {
 378                 if (x >= 0 && x < width && y >= 0 && y < height)
 379                 {
 380                         int64_t index = (transpose ? (y + x*target.w)*4 : (x + y*target.w)*4);
 381                         for (int i = 0; i < 4; ++i)
 382                                 target.pixels[index+i] = rgba[i];
 383                 }
 384
 385                 if (p < 0)
 386                         p += two_dy;
 387                 else
 388                 {
 389                         if (neg_m) --y; else ++y;
 390                         p += two_dxdy;
 391                 }
 392         } while (++x < x_end);
 393 }
 394
 395 }