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()
  33 {
  34         if (!m_shader_program.Valid())
  35                 Warn("Shader is invalid (objects are of type %d)", m_type);
  36         m_shader_program.Use();
  37         m_ibo.Bind();
  38         glDrawElements(GL_LINES, m_indexes.size()*2, GL_UNSIGNED_INT, 0);
  39 }
  40
  41
  42 /**
  43  * Default implementation for rendering using CPU
  44  */
  45 void ObjectRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target)
  46 {
  47         Error("Cannot render objects of type %d on CPU", m_type);
  48         //TODO: Render a rect or something instead?
  49 }
  50
  51 /**
  52  * Prepare index buffers for both CPU and GPU rendering to receive indexes (but don't add any yet!)
  53  */
  54 void ObjectRenderer::PrepareBuffers(unsigned max_objects)
  55 {
  56         if (m_buffer_builder != NULL) // We already have a BufferBuilder
  57         {
  58                 Fatal("Has been called before, without FinaliseBuffers being called since!");
  59         }
  60         // Empty and reserve the indexes vector (for CPU rendering)
  61         m_indexes.clear();
  62         m_indexes.reserve(max_objects); //TODO: Can probably make this smaller? Or leave it out? Do we care?
  63
  64         // Initialise and resize the ibo (for GPU rendering)
  65         m_ibo.Invalidate();
  66         m_ibo.SetUsage(GraphicsBuffer::BufferUsageStaticDraw);
  67         m_ibo.SetType(GraphicsBuffer::BufferTypeIndex);
  68         m_ibo.Resize(max_objects * 2 * sizeof(uint32_t));
  69         // BufferBuilder is used to construct the ibo
  70         m_buffer_builder = new BufferBuilder<uint32_t>(m_ibo.Map(false, true, true), m_ibo.GetSize()); // new matches delete in ObjectRenderer::FinaliseBuffers
  71
  72 }
  73
  74 /**
  75  * Add object index to the buffers for CPU and GPU rendering
  76  */
  77 void ObjectRenderer::AddObjectToBuffers(unsigned index)
  78 {
  79         if (m_buffer_builder == NULL) // No BufferBuilder!
  80         {
  81                 Fatal("Called without calling PrepareBuffers");
  82         }
  83         m_buffer_builder->Add(2*index); // ibo for GPU rendering
  84         m_buffer_builder->Add(2*index+1);
  85         m_indexes.push_back(index); // std::vector of indices for CPU rendering
  86 }
  87
  88 /**
  89  * Finalise the index buffers for CPU and GPU rendering
  90  */
  91 void ObjectRenderer::FinaliseBuffers()
  92 {
  93         if (m_buffer_builder == NULL) // No BufferBuilder!
  94         {
  95                 Fatal("Called without calling PrepareBuffers");
  96         }
  97         // For GPU rendering, UnMap the ibo
  98         m_ibo.UnMap();
  99         // ... and delete the BufferBuilder used to create it
 100         delete m_buffer_builder; // delete matches new in ObjectRenderer::PrepareBuffers
 101         m_buffer_builder = NULL;
 102
 103         // Nothing is necessary for CPU rendering
 104 }
 105
 106
 107 /**
 108  * Rectangle (filled)
 109  */
 110 void RectFilledRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target)
 111 {
 112         for (unsigned i = 0; i < m_indexes.size(); ++i)
 113         {
 114                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 115                 for (int64_t x = max(0L, bounds.x); x <= min(bounds.x+bounds.w, target.w-1); ++x)
 116                 {
 117                         for (int64_t y = max(0L, bounds.y); y <= min(bounds.y+bounds.h, target.h-1); ++y)
 118                         {
 119                                 int index = (x+target.w*y)*4;
 120                                 target.pixels[index+0] = 0;
 121                                 target.pixels[index+1] = 0;
 122                                 target.pixels[index+2] = 0;
 123                                 target.pixels[index+3] = 255;
 124                         }
 125                 }
 126         }
 127 }
 128
 129 /**
 130  * Rectangle (outine)
 131  */
 132 void RectOutlineRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target)
 133 {
 134         //Debug("Render %u outlined rectangles on CPU", m_indexes.size());
 135         for (unsigned i = 0; i < m_indexes.size(); ++i)
 136         {
 137                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 138
 139                 // Using bresenham's lines now mainly because I want to see if they work
 140                 // top
 141                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y, bounds.x+bounds.w, bounds.y, target);
 142                 // bottom
 143                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y+bounds.h, bounds.x+bounds.w, bounds.y+bounds.h, target);
 144                 // left
 145                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y, bounds.x, bounds.y+bounds.h, target);
 146                 // right
 147                 ObjectRenderer::RenderLineOnCPU(bounds.x+bounds.w, bounds.y, bounds.x+bounds.w, bounds.y+bounds.h, target);
 148
 149                 // Diagonal for testing (from bottom left to top right)
 150                 //ObjectRenderer::RenderLineOnCPU(bounds.x,bounds.y+bounds.h, bounds.x+bounds.w, bounds.y,target, C_BLUE);
 151                 //ObjectRenderer::RenderLineOnCPU(bounds.x+bounds.w, bounds.y+bounds.h, bounds.x, bounds.y, target,C_GREEN);
 152         }
 153 }
 154
 155 /**
 156  * Circle (filled)
 157  */
 158 void CircleFilledRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target)
 159 {
 160         for (unsigned i = 0; i < m_indexes.size(); ++i)
 161         {
 162                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 163                 int64_t centre_x = bounds.x + bounds.w / 2;
 164                 int64_t centre_y = bounds.y + bounds.h / 2;
 165
 166                 //Debug("Centre is %d, %d", centre_x, centre_y);
 167                 //Debug("Bounds are %d,%d,%d,%d", bounds.x, bounds.y, bounds.w, bounds.h);
 168                 //Debug("Windos is %d,%d", target.w, target.h);
 169                 for (int64_t x = max(0L, bounds.x); x <= min(bounds.x+bounds.w, target.w-1); ++x)
 170                 {
 171                         for (int64_t y = max(0L, bounds.y); y <= min(bounds.y + bounds.h, target.h-1); ++y)
 172                         {
 173                                 double dx = 2.0*(double)(x - centre_x)/(double)(bounds.w);
 174                                 double dy = 2.0*(double)(y - centre_y)/(double)(bounds.h);
 175                                 int64_t index = (x+target.w*y)*4;
 176
 177                                 if (dx*dx + dy*dy <= 1.0)
 178                                 {
 179                                         target.pixels[index+0] = 0;
 180                                         target.pixels[index+1] = 0;
 181                                         target.pixels[index+2] = 0;
 182                                         target.pixels[index+3] = 255;
 183
 184                                 }
 185                         }
 186                 }
 187         }
 188 }
 189
 190 Rect ObjectRenderer::CPURenderBounds(const Rect & bounds, const View & view, const CPURenderTarget & target)
 191 {
 192         Rect result = view.TransformToViewCoords(bounds);
 193         result.x *= Real(target.w);
 194         result.y *= Real(target.h);
 195         result.w *= Real(target.w);
 196         result.h *= Real(target.h);
 197         return result;
 198 }
 199
 200
 201 /**
 202  * Bezier curve
 203  * Not sure how to apply De'Casteljau, will just use a bunch of Bresnham lines for now.
 204  */
 205 void BezierRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target)
 206 {
 207         //Warn("Rendering Beziers on CPU. Things may explode.");
 208         for (unsigned i = 0; i < m_indexes.size(); ++i)
 209         {
 210                 Rect bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 211                 PixelBounds pix_bounds(bounds);
 212
 213
 214                 Bezier control(objects.beziers[objects.data_indices[m_indexes[i]]], bounds);
 215                 //Debug("%s -> %s via %s", objects.beziers[objects.data_indices[m_indexes[i]]].Str().c_str(), control.Str().c_str(), bounds.Str().c_str());
 216                 // Draw a rectangle around the bezier for debugging the coord transforms
 217                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y, pix_bounds.x+pix_bounds.w, pix_bounds.y, target);
 218                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y+pix_bounds.h, pix_bounds.x+pix_bounds.w, pix_bounds.y+pix_bounds.h, target);
 219                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y, pix_bounds.x, pix_bounds.y+pix_bounds.h, target);
 220                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x+pix_bounds.w, pix_bounds.y, pix_bounds.x+pix_bounds.w, pix_bounds.y+pix_bounds.h, target);
 221
 222                 // Draw lines between the control points for debugging
 223                 //ObjectRenderer::RenderLineOnCPU((int64_t)control.x0, (int64_t)control.y0, (int64_t)control.x1, (int64_t)control.y1,target);
 224                 //ObjectRenderer::RenderLineOnCPU((int64_t)control.x1, (int64_t)control.y1, (int64_t)control.x2, (int64_t)control.y2,target);
 225
 226
 227
 228                 Real x[2]; Real y[2];
 229                 control.Evaluate(x[0], y[0], Real(0));
 230                 int64_t blen = max(2L, min(100L, pix_bounds.w));
 231                 Real invblen(1); invblen /= blen;
 232                 Debug("Using %li lines, inverse %f", blen, Double(invblen));
 233                 for (int64_t j = 1; j <= blen; ++j)
 234                 {
 235                         control.Evaluate(x[j % 2],y[j % 2], invblen*j);
 236                         ObjectRenderer::RenderLineOnCPU((int64_t)Double(x[0]),(int64_t)Double(y[0]), (int64_t)Double(x[1]),(int64_t)Double(y[1]), target);
 237                 }
 238
 239                 /*
 240                 Real u(0);
 241                 while (u < Real(1))
 242                 {
 243                         u += Real(1e-6);
 244                         Real x; Real y; control.Evaluate(x,y,u);
 245                         int64_t index = ((int64_t)x + (int64_t)y*target.w)*4;
 246                         if (index >= 0 && index < 4*(target.w*target.h))
 247                         {
 248                                 target.pixels[index+0] = 0;
 249                                 target.pixels[index+1] = 0;
 250                                 target.pixels[index+2] = 0;
 251                                 target.pixels[index+3] = 255;
 252                         }
 253                 }
 254                 */
 255
 256         }
 257 }
 258
 259 void BezierRenderer::PrepareBezierGPUBuffer(const Objects& objects)
 260 {
 261         m_bezier_coeffs.SetType(GraphicsBuffer::BufferTypeTexture);
 262         m_bezier_coeffs.SetUsage(GraphicsBuffer::BufferUsageDynamicDraw);
 263         m_bezier_coeffs.Resize(objects.beziers.size()*sizeof(GPUBezierCoeffs));
 264         BufferBuilder<GPUBezierCoeffs> builder(m_bezier_coeffs.Map(false, true, true), m_bezier_coeffs.GetSize());
 265
 266         for (auto bez : objects.beziers)
 267         {
 268                 GPUBezierCoeffs coeffs = {
 269                         Float(bez.x0), Float(bez.y0),
 270                         Float(bez.x1 - bez.x0), Float(bez.y1 - bez.y0),
 271                         Float(bez.x2 - bez.x0), Float(bez.y2 - bez.y0)
 272                         };
 273                 builder.Add(coeffs);
 274         }
 275         m_bezier_coeffs.UnMap();
 276         glGenTextures(1, &m_bezier_buffer_texture);
 277         glBindTexture(GL_TEXTURE_BUFFER, m_bezier_buffer_texture);
 278         glTexBuffer(GL_TEXTURE_BUFFER, GL_RG32F, m_bezier_coeffs.GetHandle());
 279
 280         m_bezier_ids.SetType(GraphicsBuffer::BufferTypeTexture);
 281         m_bezier_ids.SetUsage(GraphicsBuffer::BufferUsageDynamicDraw);
 282         m_bezier_ids.Upload(objects.data_indices.size() * sizeof(uint32_t), &objects.data_indices[0]);
 283
 284         glGenTextures(1, &m_bezier_id_buffer_texture);
 285         glActiveTexture(GL_TEXTURE1);
 286         glBindTexture(GL_TEXTURE_BUFFER, m_bezier_id_buffer_texture);
 287         glTexBuffer(GL_TEXTURE_BUFFER, GL_R32I, m_bezier_ids.GetHandle());
 288         glActiveTexture(GL_TEXTURE0);
 289 }
 290
 291 void BezierRenderer::RenderUsingGPU()
 292 {
 293         if (!m_shader_program.Valid())
 294                 Warn("Shader is invalid (objects are of type %d)", m_type);
 295         m_shader_program.Use();
 296         glUniform1i(m_shader_program.GetUniformLocation("bezier_buffer_texture"), 0);
 297         glUniform1i(m_shader_program.GetUniformLocation("bezier_id_buffer_texture"), 1);
 298         m_ibo.Bind();
 299         glDrawElements(GL_LINES, m_indexes.size()*2, GL_UNSIGNED_INT, 0);
 300 }
 301
 302 /**
 303  * For debug, save pixels to bitmap
 304  */
 305 void ObjectRenderer::SaveBMP(const CPURenderTarget & target, const char * filename)
 306 {
 307         SDL_Surface * surf = SDL_CreateRGBSurfaceFrom(target.pixels, target.w, target.h, 8*4, target.w*4,
 308         #if SDL_BYTEORDER == SDL_LIL_ENDIAN
 309                 0x000000ff, 0x0000ff00, 0x00ff0000, 0xff000000
 310         #else
 311                 0xff000000, 0x00ff0000, 0x0000ff00, 0x000000ff
 312         #endif //SDL_BYTEORDER
 313         );
 314         if (surf == NULL)
 315                 Fatal("SDL_CreateRGBSurfaceFrom(pixels...) failed - %s", SDL_GetError());
 316         if (SDL_SaveBMP(surf, filename) != 0)
 317                 Fatal("SDL_SaveBMP failed - %s", SDL_GetError());
 318
 319         // Cleanup
 320         SDL_FreeSurface(surf);
 321 }
 322
 323 /**
 324  * Bresenham's lines
 325  */
 326 void ObjectRenderer::RenderLineOnCPU(int64_t x0, int64_t y0, int64_t x1, int64_t y1, const CPURenderTarget & target, const Colour & colour, bool transpose)
 327 {
 328         int64_t dx = x1 - x0;
 329         int64_t dy = y1 - y0;
 330         bool neg_m = (dy*dx < 0);
 331         dy = abs(dy);
 332         dx = abs(dx);
 333
 334         // If positive slope > 1, just swap x and y
 335         if (dy > dx)
 336         {
 337                 RenderLineOnCPU(y0,x0,y1,x1,target,colour,!transpose);
 338                 return;
 339         }
 340
 341         int64_t two_dy = 2*dy;
 342         int64_t p = two_dy - dx;
 343         int64_t two_dxdy = 2*(dy-dx);
 344         int64_t x; int64_t y; int64_t x_end;
 345         int64_t width = (transpose ? target.h : target.w);
 346         int64_t height = (transpose ? target.w : target.h);
 347
 348         uint8_t rgba[4];
 349         rgba[0] = 255*colour.r;
 350         rgba[1] = 255*colour.g;
 351         rgba[2] = 255*colour.b;
 352         rgba[3] = 255*colour.a;
 353
 354         if (x0 > x1)
 355         {
 356                 x = x1;
 357                 y = y1;
 358                 x_end = x0;
 359         }
 360         else
 361         {
 362                 x = x0;
 363                 y = y0;
 364                 x_end = x1;
 365         }
 366
 367         if (x < 0)
 368         {
 369                 if (x_end < 0) return;
 370                 y = (neg_m ? y - (dy*-x)/dx : y + (dy*-x)/dx);
 371                 x = 0;
 372         }
 373
 374         if (x_end > width)
 375         {
 376                 if (x > width) return;
 377                 x_end = width-1;
 378         }
 379
 380         // TODO: Avoid extra inner conditionals
 381         do
 382         {
 383                 if (x >= 0 && x < width && y >= 0 && y < height)
 384                 {
 385                         int64_t index = (transpose ? (y + x*target.w)*4 : (x + y*target.w)*4);
 386                         for (int i = 0; i < 4; ++i)
 387                                 target.pixels[index+i] = rgba[i];
 388                 }
 389
 390                 if (p < 0)
 391                         p += two_dy;
 392                 else
 393                 {
 394                         if (neg_m) --y; else ++y;
 395                         p += two_dxdy;
 396                 }
 397         } while (++x < x_end);
 398 }
 399
 400 }