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*2) first_index += 2;
  36         unsigned last_index = first_index;
  37         while (m_indexes[last_index] < last_obj_id*2) last_index += 2;
  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)
  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)
 114 {
 115         for (unsigned i = 0; i < m_indexes.size(); ++i)
 116         {
 117                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 118                 for (int64_t x = max(0L, bounds.x); x <= min(bounds.x+bounds.w, target.w-1); ++x)
 119                 {
 120                         for (int64_t y = max(0L, bounds.y); y <= min(bounds.y+bounds.h, target.h-1); ++y)
 121                         {
 122                                 int index = (x+target.w*y)*4;
 123                                 target.pixels[index+0] = 0;
 124                                 target.pixels[index+1] = 0;
 125                                 target.pixels[index+2] = 0;
 126                                 target.pixels[index+3] = 255;
 127                         }
 128                 }
 129         }
 130 }
 131
 132 /**
 133  * Rectangle (outine)
 134  */
 135 void RectOutlineRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target)
 136 {
 137         //Debug("Render %u outlined rectangles on CPU", m_indexes.size());
 138         for (unsigned i = 0; i < m_indexes.size(); ++i)
 139         {
 140                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 141
 142                 // Using bresenham's lines now mainly because I want to see if they work
 143                 // top
 144                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y, bounds.x+bounds.w, bounds.y, target);
 145                 // bottom
 146                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y+bounds.h, bounds.x+bounds.w, bounds.y+bounds.h, target);
 147                 // left
 148                 ObjectRenderer::RenderLineOnCPU(bounds.x, bounds.y, bounds.x, bounds.y+bounds.h, target);
 149                 // right
 150                 ObjectRenderer::RenderLineOnCPU(bounds.x+bounds.w, bounds.y, bounds.x+bounds.w, bounds.y+bounds.h, target);
 151
 152                 // Diagonal for testing (from bottom left to top right)
 153                 //ObjectRenderer::RenderLineOnCPU(bounds.x,bounds.y+bounds.h, bounds.x+bounds.w, bounds.y,target, C_BLUE);
 154                 //ObjectRenderer::RenderLineOnCPU(bounds.x+bounds.w, bounds.y+bounds.h, bounds.x, bounds.y, target,C_GREEN);
 155         }
 156 }
 157
 158 /**
 159  * Circle (filled)
 160  */
 161 void CircleFilledRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target)
 162 {
 163         for (unsigned i = 0; i < m_indexes.size(); ++i)
 164         {
 165                 PixelBounds bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 166                 int64_t centre_x = bounds.x + bounds.w / 2;
 167                 int64_t centre_y = bounds.y + bounds.h / 2;
 168
 169                 //Debug("Centre is %d, %d", centre_x, centre_y);
 170                 //Debug("Bounds are %d,%d,%d,%d", bounds.x, bounds.y, bounds.w, bounds.h);
 171                 //Debug("Windos is %d,%d", target.w, target.h);
 172                 for (int64_t x = max(0L, bounds.x); x <= min(bounds.x+bounds.w, target.w-1); ++x)
 173                 {
 174                         for (int64_t y = max(0L, bounds.y); y <= min(bounds.y + bounds.h, target.h-1); ++y)
 175                         {
 176                                 double dx = 2.0*(double)(x - centre_x)/(double)(bounds.w);
 177                                 double dy = 2.0*(double)(y - centre_y)/(double)(bounds.h);
 178                                 int64_t index = (x+target.w*y)*4;
 179
 180                                 if (dx*dx + dy*dy <= 1.0)
 181                                 {
 182                                         target.pixels[index+0] = 0;
 183                                         target.pixels[index+1] = 0;
 184                                         target.pixels[index+2] = 0;
 185                                         target.pixels[index+3] = 255;
 186
 187                                 }
 188                         }
 189                 }
 190         }
 191 }
 192
 193 Rect ObjectRenderer::CPURenderBounds(const Rect & bounds, const View & view, const CPURenderTarget & target)
 194 {
 195         Rect result = view.TransformToViewCoords(bounds);
 196         result.x *= Real(target.w);
 197         result.y *= Real(target.h);
 198         result.w *= Real(target.w);
 199         result.h *= Real(target.h);
 200         return result;
 201 }
 202
 203
 204 /**
 205  * Bezier curve
 206  * Not sure how to apply De'Casteljau, will just use a bunch of Bresnham lines for now.
 207  */
 208 void BezierRenderer::RenderUsingCPU(const Objects & objects, const View & view, const CPURenderTarget & target)
 209 {
 210         //Warn("Rendering Beziers on CPU. Things may explode.");
 211         for (unsigned i = 0; i < m_indexes.size(); ++i)
 212         {
 213                 Rect bounds(CPURenderBounds(objects.bounds[m_indexes[i]], view, target));
 214                 PixelBounds pix_bounds(bounds);
 215
 216
 217                 Bezier control(objects.beziers[objects.data_indices[m_indexes[i]]], bounds);
 218                 //Debug("%s -> %s via %s", objects.beziers[objects.data_indices[m_indexes[i]]].Str().c_str(), control.Str().c_str(), bounds.Str().c_str());
 219                 // Draw a rectangle around the bezier for debugging the coord transforms
 220                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y, pix_bounds.x+pix_bounds.w, pix_bounds.y, target);
 221                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y+pix_bounds.h, pix_bounds.x+pix_bounds.w, pix_bounds.y+pix_bounds.h, target);
 222                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x, pix_bounds.y, pix_bounds.x, pix_bounds.y+pix_bounds.h, target);
 223                 //ObjectRenderer::RenderLineOnCPU(pix_bounds.x+pix_bounds.w, pix_bounds.y, pix_bounds.x+pix_bounds.w, pix_bounds.y+pix_bounds.h, target);
 224
 225                 // Draw lines between the control points for debugging
 226                 //ObjectRenderer::RenderLineOnCPU((int64_t)control.x0, (int64_t)control.y0, (int64_t)control.x1, (int64_t)control.y1,target);
 227                 //ObjectRenderer::RenderLineOnCPU((int64_t)control.x1, (int64_t)control.y1, (int64_t)control.x2, (int64_t)control.y2,target);
 228
 229
 230
 231                 Real x[2]; Real y[2];
 232                 control.Evaluate(x[0], y[0], Real(0));
 233                 int64_t blen = max(2L, min(100L, pix_bounds.w));
 234                 Real invblen(1); invblen /= blen;
 235                 Debug("Using %li lines, inverse %f", blen, Double(invblen));
 236                 for (int64_t j = 1; j <= blen; ++j)
 237                 {
 238                         control.Evaluate(x[j % 2],y[j % 2], invblen*j);
 239                         ObjectRenderer::RenderLineOnCPU((int64_t)Double(x[0]),(int64_t)Double(y[0]), (int64_t)Double(x[1]),(int64_t)Double(y[1]), target);
 240                 }
 241
 242                 /*
 243                 Real u(0);
 244                 while (u < Real(1))
 245                 {
 246                         u += Real(1e-6);
 247                         Real x; Real y; control.Evaluate(x,y,u);
 248                         int64_t index = ((int64_t)x + (int64_t)y*target.w)*4;
 249                         if (index >= 0 && index < 4*(target.w*target.h))
 250                         {
 251                                 target.pixels[index+0] = 0;
 252                                 target.pixels[index+1] = 0;
 253                                 target.pixels[index+2] = 0;
 254                                 target.pixels[index+3] = 255;
 255                         }
 256                 }
 257                 */
 258
 259         }
 260 }
 261
 262 void BezierRenderer::PrepareBezierGPUBuffer(const Objects& objects)
 263 {
 264         m_bezier_coeffs.SetType(GraphicsBuffer::BufferTypeTexture);
 265         m_bezier_coeffs.SetUsage(GraphicsBuffer::BufferUsageDynamicDraw);
 266         m_bezier_coeffs.Resize(objects.beziers.size()*sizeof(GPUBezierCoeffs));
 267         BufferBuilder<GPUBezierCoeffs> builder(m_bezier_coeffs.Map(false, true, true), m_bezier_coeffs.GetSize());
 268
 269         for (auto bez : objects.beziers)
 270         {
 271                 GPUBezierCoeffs coeffs = {
 272                         Float(bez.x0), Float(bez.y0),
 273                         Float(bez.x1 - bez.x0), Float(bez.y1 - bez.y0),
 274                         Float(bez.x2 - bez.x0), Float(bez.y2 - bez.y0)
 275                         };
 276                 builder.Add(coeffs);
 277         }
 278         m_bezier_coeffs.UnMap();
 279         glGenTextures(1, &m_bezier_buffer_texture);
 280         glBindTexture(GL_TEXTURE_BUFFER, m_bezier_buffer_texture);
 281         glTexBuffer(GL_TEXTURE_BUFFER, GL_RG32F, m_bezier_coeffs.GetHandle());
 282
 283         m_bezier_ids.SetType(GraphicsBuffer::BufferTypeTexture);
 284         m_bezier_ids.SetUsage(GraphicsBuffer::BufferUsageDynamicDraw);
 285         m_bezier_ids.Upload(objects.data_indices.size() * sizeof(uint32_t), &objects.data_indices[0]);
 286
 287         glGenTextures(1, &m_bezier_id_buffer_texture);
 288         glActiveTexture(GL_TEXTURE1);
 289         glBindTexture(GL_TEXTURE_BUFFER, m_bezier_id_buffer_texture);
 290         glTexBuffer(GL_TEXTURE_BUFFER, GL_R32I, m_bezier_ids.GetHandle());
 291         glActiveTexture(GL_TEXTURE0);
 292 }
 293
 294 void BezierRenderer::RenderUsingGPU(unsigned first_obj_id, unsigned last_obj_id)
 295 {
 296         if (!m_shader_program.Valid())
 297                 Warn("Shader is invalid (objects are of type %d)", m_type);
 298
 299         unsigned first_index = 0;
 300         while (m_indexes[first_index] < first_obj_id*2) first_index += 2;
 301         unsigned last_index = first_index;
 302         while (m_indexes[last_index] < last_obj_id*2) last_index += 2;
 303
 304         m_shader_program.Use();
 305         glUniform1i(m_shader_program.GetUniformLocation("bezier_buffer_texture"), 0);
 306         glUniform1i(m_shader_program.GetUniformLocation("bezier_id_buffer_texture"), 1);
 307         m_ibo.Bind();
 308         glDrawElements(GL_LINES, (last_index-first_index)*2, GL_UNSIGNED_INT, (GLvoid*)(first_index*sizeof(uint32_t)));
 309 }
 310
 311 /**
 312  * For debug, save pixels to bitmap
 313  */
 314 void ObjectRenderer::SaveBMP(const CPURenderTarget & target, const char * filename)
 315 {
 316         SDL_Surface * surf = SDL_CreateRGBSurfaceFrom(target.pixels, target.w, target.h, 8*4, target.w*4,
 317         #if SDL_BYTEORDER == SDL_LIL_ENDIAN
 318                 0x000000ff, 0x0000ff00, 0x00ff0000, 0xff000000
 319         #else
 320                 0xff000000, 0x00ff0000, 0x0000ff00, 0x000000ff
 321         #endif //SDL_BYTEORDER
 322         );
 323         if (surf == NULL)
 324                 Fatal("SDL_CreateRGBSurfaceFrom(pixels...) failed - %s", SDL_GetError());
 325         if (SDL_SaveBMP(surf, filename) != 0)
 326                 Fatal("SDL_SaveBMP failed - %s", SDL_GetError());
 327
 328         // Cleanup
 329         SDL_FreeSurface(surf);
 330 }
 331
 332 /**
 333  * Bresenham's lines
 334  */
 335 void ObjectRenderer::RenderLineOnCPU(int64_t x0, int64_t y0, int64_t x1, int64_t y1, const CPURenderTarget & target, const Colour & colour, bool transpose)
 336 {
 337         int64_t dx = x1 - x0;
 338         int64_t dy = y1 - y0;
 339         bool neg_m = (dy*dx < 0);
 340         dy = abs(dy);
 341         dx = abs(dx);
 342
 343         // If positive slope > 1, just swap x and y
 344         if (dy > dx)
 345         {
 346                 RenderLineOnCPU(y0,x0,y1,x1,target,colour,!transpose);
 347                 return;
 348         }
 349
 350         int64_t two_dy = 2*dy;
 351         int64_t p = two_dy - dx;
 352         int64_t two_dxdy = 2*(dy-dx);
 353         int64_t x; int64_t y; int64_t x_end;
 354         int64_t width = (transpose ? target.h : target.w);
 355         int64_t height = (transpose ? target.w : target.h);
 356
 357         uint8_t rgba[4];
 358         rgba[0] = 255*colour.r;
 359         rgba[1] = 255*colour.g;
 360         rgba[2] = 255*colour.b;
 361         rgba[3] = 255*colour.a;
 362
 363         if (x0 > x1)
 364         {
 365                 x = x1;
 366                 y = y1;
 367                 x_end = x0;
 368         }
 369         else
 370         {
 371                 x = x0;
 372                 y = y0;
 373                 x_end = x1;
 374         }
 375
 376         if (x < 0)
 377         {
 378                 if (x_end < 0) return;
 379                 y = (neg_m ? y - (dy*-x)/dx : y + (dy*-x)/dx);
 380                 x = 0;
 381         }
 382
 383         if (x_end > width)
 384         {
 385                 if (x > width) return;
 386                 x_end = width-1;
 387         }
 388
 389         // TODO: Avoid extra inner conditionals
 390         do
 391         {
 392                 if (x >= 0 && x < width && y >= 0 && y < height)
 393                 {
 394                         int64_t index = (transpose ? (y + x*target.w)*4 : (x + y*target.w)*4);
 395                         for (int i = 0; i < 4; ++i)
 396                                 target.pixels[index+i] = rgba[i];
 397                 }
 398
 399                 if (p < 0)
 400                         p += two_dy;
 401                 else
 402                 {
 403                         if (neg_m) --y; else ++y;
 404                         p += two_dxdy;
 405                 }
 406         } while (++x < x_end);
 407 }
 408
 409 }