src/screen.cpp

   1 #include "common.h"
   2 #include "screen.h"
   3
   4 #include "gl_core44.h"
   5 #include <fcntl.h> // for access(2)
   6 #include <unistd.h> // for access(2)
   7
   8 #include "bufferbuilder.h"
   9 #include "shaderprogram.h"
  10
  11 #define BASICTEX_VERT "shaders/basictex_vert.glsl"
  12 #define BASICTEX_FRAG "shaders/basictex_frag.glsl"
  13
  14 using namespace IPDF;
  15 using namespace std;
  16
  17 static void opengl_debug_callback(GLenum source, GLenum type, GLuint id, GLenum severity, GLsizei length, const GLchar* msg, const void *data)
  18 {
  19         Error("OpenGL Error (%d): %s", id, msg);
  20 }
  21
  22
  23 Screen::Screen()
  24 {
  25
  26         SDL_Init(SDL_INIT_VIDEO);
  27         m_window = SDL_CreateWindow("IPDF", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
  28                         800, 600, SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE);
  29
  30         if (!m_window)
  31         {
  32                 Fatal("Couldn't create window!");
  33         }
  34
  35         SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
  36         SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 1);
  37         SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, SDL_GL_CONTEXT_DEBUG_FLAG);
  38         SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
  39
  40         m_gl_context = SDL_GL_CreateContext(m_window);
  41
  42         ogl_LoadFunctions();
  43
  44         // Why is this so horribly broken?
  45         if (ogl_IsVersionGEQ(3,0))
  46         {
  47                 Fatal("We require OpenGL 3.1, but you have version %d.%d!",ogl_GetMajorVersion(), ogl_GetMinorVersion());
  48         }
  49
  50         if (!SDL_GL_ExtensionSupported("GL_ARB_shading_language_420pack"))
  51         {
  52                 Fatal("Your system does not support the ARB_shading_language_420pack extension, which is required.");
  53         }
  54
  55         if (!SDL_GL_ExtensionSupported("GL_ARB_explicit_attrib_location"))
  56         {
  57                 Fatal("Your system does not support the ARB_explicit_attrib_location extension, which is required.");
  58         }
  59
  60         m_frame_begin_time = SDL_GetPerformanceCounter();
  61         m_last_frame_time = 0;
  62         m_last_frame_gpu_timer = 0;
  63         glGenQueries(1, &m_frame_gpu_timer);
  64         glBeginQuery(GL_TIME_ELAPSED, m_frame_gpu_timer);
  65
  66         glDebugMessageCallback(opengl_debug_callback, 0);
  67
  68         GLuint default_vao;
  69         glGenVertexArrays(1, &default_vao);
  70         glBindVertexArray(default_vao);
  71
  72         m_texture_prog.InitialiseShaders(BASICTEX_VERT, BASICTEX_FRAG);
  73         m_texture_prog.Use();
  74
  75         // We always want to use the texture bound to texture unit 0.
  76         GLint texture_uniform_location = m_texture_prog.GetUniformLocation("tex");
  77         glUniform1i(texture_uniform_location, 0);
  78
  79         m_font_prog.InitialiseShaders(BASICTEX_VERT, "shaders/fonttex_frag.glsl");
  80         m_font_prog.Use();
  81
  82         // We always want to use the texture bound to texture unit 0.
  83         GLint font_texture_uniform_location = m_font_prog.GetUniformLocation("tex");
  84         glUniform1i(font_texture_uniform_location, 0);
  85         m_colour_uniform_location = m_font_prog.GetUniformLocation("colour");
  86
  87         m_viewport_ubo.SetUsage(GraphicsBuffer::BufferUsageDynamicDraw);
  88         m_viewport_ubo.SetType(GraphicsBuffer::BufferTypeUniform);
  89
  90         m_debug_font_atlas = 0;
  91
  92         m_view = NULL;
  93         ResizeViewport(800, 600);
  94
  95         Clear();
  96         Present();
  97
  98
  99 }
 100
 101 Screen::~Screen()
 102 {
 103         SDL_GL_DeleteContext(m_gl_context);
 104         SDL_DestroyWindow(m_window);
 105         SDL_Quit();
 106 }
 107
 108 void Screen::Clear(float r, float g, float b, float a)
 109 {
 110         glClearColor(r,g,b,a);
 111         glClear(GL_COLOR_BUFFER_BIT);
 112         DebugFontClear();
 113 }
 114
 115 void Screen::ResizeViewport(int width, int height)
 116 {
 117         glViewport(0, 0, width, height);
 118         m_viewport_width = width;
 119         m_viewport_height = height;
 120         GLfloat viewportfloats[] = {(float)width, (float)height};
 121         m_viewport_ubo.Upload(sizeof(float)*2, viewportfloats);
 122 }
 123
 124 bool Screen::PumpEvents()
 125 {
 126         SDL_Event evt;
 127         bool no_quit_requested = true;
 128         while (SDL_PollEvent(&evt))
 129         {
 130                 switch (evt.type)
 131                 {
 132                 case SDL_QUIT:
 133                         no_quit_requested = false;
 134                         break;
 135                 case SDL_WINDOWEVENT:
 136                         switch (evt.window.event)
 137                         {
 138                         case SDL_WINDOWEVENT_RESIZED:
 139                         case SDL_WINDOWEVENT_SIZE_CHANGED:
 140                                 ResizeViewport(evt.window.data1, evt.window.data2);
 141                                 break;
 142                         }
 143                         break;
 144                 case SDL_MOUSEMOTION:
 145                         m_last_mouse_x = evt.motion.x;
 146                         m_last_mouse_y = evt.motion.y;
 147                         if (m_mouse_handler)
 148                         {
 149                                 m_mouse_handler(evt.motion.x, evt.motion.y,evt.motion.state, 0, this, m_view);
 150                         }
 151                         break;
 152                 case SDL_MOUSEBUTTONDOWN:
 153                 case SDL_MOUSEBUTTONUP:
 154                         m_last_mouse_x = evt.button.x;
 155                         m_last_mouse_y = evt.button.y;
 156                         if (m_mouse_handler)
 157                         {
 158                                 m_mouse_handler(evt.button.x, evt.button.y, evt.button.state?evt.button.button:0, 0, this, m_view);
 159                         }
 160                         break;
 161                 case SDL_MOUSEWHEEL:
 162                         if (m_mouse_handler)
 163                         {
 164                                 m_mouse_handler(m_last_mouse_x, m_last_mouse_y, 0, evt.wheel.y, this, m_view);
 165                         }
 166                         break;
 167                 case SDL_KEYDOWN:
 168                 {
 169                         Debug("Key %c down", (char)evt.key.keysym.sym);
 170                         if (isalnum((char)evt.key.keysym.sym))
 171                         {
 172                                 char filename[] = "0.bmp";
 173                                 filename[0] = (char)evt.key.keysym.sym;
 174                                 ScreenShot(filename);
 175                         }
 176                         break;
 177                 }
 178                 default:
 179                         break;
 180                 }
 181         }
 182         return no_quit_requested;
 183 }
 184
 185 void Screen::SetMouseCursor(Screen::MouseCursors cursor)
 186 {
 187         SDL_SystemCursor system_cursor_id = SDL_SYSTEM_CURSOR_ARROW;
 188         switch (cursor)
 189         {
 190         case CursorArrow: system_cursor_id = SDL_SYSTEM_CURSOR_ARROW; break;
 191         case CursorWait: system_cursor_id = SDL_SYSTEM_CURSOR_WAIT; break;
 192         case CursorWaitArrow: system_cursor_id = SDL_SYSTEM_CURSOR_WAITARROW; break;
 193         case CursorMove: system_cursor_id = SDL_SYSTEM_CURSOR_SIZEALL; break;
 194         case CursorHand: system_cursor_id = SDL_SYSTEM_CURSOR_HAND; break;
 195         default: break;
 196         }
 197         SDL_Cursor *system_cursor = SDL_CreateSystemCursor(system_cursor_id);
 198         SDL_SetCursor(system_cursor);
 199         //TODO: Check if we need to free the system cursors.
 200 }
 201
 202 void Screen::Present()
 203 {
 204         if (m_debug_font_atlas)
 205                 DebugFontFlush();
 206         m_last_frame_time = SDL_GetPerformanceCounter() - m_frame_begin_time;
 207         glEndQuery(GL_TIME_ELAPSED);
 208         SDL_GL_SwapWindow(m_window);
 209         m_frame_begin_time = SDL_GetPerformanceCounter();
 210         if (m_last_frame_gpu_timer)
 211                 glDeleteQueries(1, &m_last_frame_gpu_timer);
 212         m_last_frame_gpu_timer = m_frame_gpu_timer;
 213         glGenQueries(1, &m_frame_gpu_timer);
 214         glBeginQuery(GL_TIME_ELAPSED, m_frame_gpu_timer);
 215 }
 216
 217 double Screen::GetLastFrameTimeGPU() const
 218 {
 219         if (!m_last_frame_gpu_timer)
 220                 return 0;
 221         uint64_t frame_time_ns;
 222         glGetQueryObjectui64v(m_last_frame_gpu_timer, GL_QUERY_RESULT, &frame_time_ns);
 223         return frame_time_ns/1000000000.0;
 224 }
 225
 226 void Screen::RenderPixels(int x, int y, int w, int h, uint8_t *pixels) const
 227 {
 228         GLenum texture_format = GL_RGBA;
 229
 230         m_texture_prog.Use();
 231         GraphicsBuffer quad_vertex_buffer;
 232         quad_vertex_buffer.SetUsage(GraphicsBuffer::BufferUsageStaticDraw);
 233         quad_vertex_buffer.SetType(GraphicsBuffer::BufferTypeVertex);
 234         //rectangular texture == 2 triangles
 235         GLfloat quad[] = {
 236                 0, 0, (float)x, (float)y,
 237                 1, 0, (float)(x+w), (float)y,
 238                 0, 1, (float)x, (float)(y+h),
 239                 1, 1, (float)(x+w), (float)(y+h)
 240         };
 241         quad_vertex_buffer.Upload(sizeof(GLfloat) * 16, quad);
 242         quad_vertex_buffer.Bind();
 243         m_viewport_ubo.Bind();
 244
 245         glUniform4f(m_colour_uniform_location, 1.0f, 1.0f, 1.0f, 1.0f);
 246
 247         GLuint texID;
 248         glGenTextures(1, &texID);
 249         glBindTexture(GL_TEXTURE_2D, texID);
 250
 251         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 252         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 253         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
 254         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
 255
 256         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, w, h, 0, texture_format, GL_UNSIGNED_BYTE, pixels);
 257
 258         glEnableVertexAttribArray(0);
 259         glEnableVertexAttribArray(1);
 260         glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 4*sizeof(float), (void*)(2*sizeof(float)));
 261         glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 4*sizeof(float), 0);
 262         glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
 263         glDisableVertexAttribArray(1);
 264         glDisableVertexAttribArray(0);
 265
 266 }
 267
 268 void Screen::ScreenShot(const char * filename) const
 269 {
 270         Debug("Attempting to save BMP to file %s", filename);
 271
 272         int w = ViewportWidth();
 273         int h = ViewportHeight();
 274         unsigned char * pixels = new unsigned char[w*h*4];
 275         if (pixels == NULL)
 276                 Fatal("Failed to allocate %d x %d x 4 = %d pixel array", w, h, w*h*4);
 277
 278         for (int y = 0; y < h; ++y)
 279         {
 280                 glReadPixels(0,h-y-1,w, 1, GL_RGBA, GL_UNSIGNED_BYTE, &pixels[y*w*4]);
 281         }
 282
 283 #if SDL_BYTEORDER == SDL_LIL_ENDIAN
 284         SDL_Surface * surf = SDL_CreateRGBSurfaceFrom(pixels, w, h, 8*4, w*4, 0x000000ff,0x0000ff00,0x00ff0000,0xff000000);
 285 #else
 286         SDL_Surface * surf = SDL_CreateRGBSurfaceFrom(pixels, w, h, 8*4, w*4, 0xff000000,0x00ff0000,0x0000ff00,0x000000ff);
 287 #endif
 288         if (surf == NULL)
 289                 Fatal("Failed to create SDL_Surface from pixel data - %s", SDL_GetError());
 290
 291         GLenum texture_format = (surf->format->Rmask == 0x000000FF) ? GL_RGBA : GL_BGRA;
 292         Debug("SDL_Surface %d BytesPerPixel, format %d (RGB = %d, BGR = %d, RGBA = %d, BGRA = %d)", surf->format->BytesPerPixel, texture_format, GL_RGB, GL_BGR, GL_RGBA, GL_BGRA);
 293
 294         if (SDL_SaveBMP(surf, filename) != 0)
 295                 Fatal("SDL_SaveBMP failed - %s", SDL_GetError());
 296
 297         SDL_FreeSurface(surf);
 298         delete [] pixels;
 299         Debug("Succeeded!");
 300 }
 301
 302 /**
 303  * Render a BMP
 304  * NOT PART OF THE DOCUMENT FORMAT
 305  */
 306 void Screen::RenderBMP(const char * filename) const
 307 {
 308         if (access(filename, R_OK) == -1)
 309         {
 310                 Error("No such file \"%s\" - Nothing to render - You might have done this deliberately?", filename);
 311                 return;
 312         }
 313         SDL_Surface * bmp = SDL_LoadBMP(filename);
 314         if (bmp == NULL)
 315                 Fatal("Failed to load BMP from %s - %s", filename, SDL_GetError());
 316
 317         int w = bmp->w;
 318         int h = bmp->h;
 319
 320         GLenum texture_format = GL_RGBA;
 321         switch (bmp->format->BytesPerPixel)
 322         {
 323                 case 4: //contains alpha
 324                         texture_format = (bmp->format->Rmask == 0x000000FF) ? GL_RGBA : GL_BGRA;
 325                         break;
 326                 case 3: //does not contain alpha
 327                         texture_format = (bmp->format->Rmask == 0x000000FF) ? GL_RGB : GL_BGR;
 328                         break;
 329                 default:
 330                         Fatal("Could not understand SDL_Surface format (%d colours)", bmp->format->BytesPerPixel);
 331                         break;
 332         }
 333
 334         //Debug("SDL_Surface %d BytesPerPixel, format %d (RGB = %d, BGR = %d, RGBA = %d, BGRA = %d)", bmp->format->BytesPerPixel, texture_format, GL_RGB, GL_BGR, GL_RGBA, GL_BGRA);
 335
 336         m_texture_prog.Use();
 337         GraphicsBuffer quad_vertex_buffer;
 338         quad_vertex_buffer.SetUsage(GraphicsBuffer::BufferUsageStaticDraw);
 339         quad_vertex_buffer.SetType(GraphicsBuffer::BufferTypeVertex);
 340         GLfloat quad[] = {
 341                 0, 0, 0, 0,
 342                 1, 0, (float)ViewportWidth(), 0,
 343                 1, 1, (float)ViewportWidth(), (float)ViewportHeight(),
 344                 0, 1, 0, (float)ViewportHeight()
 345         };
 346         quad_vertex_buffer.Upload(sizeof(GLfloat) * 16, quad);
 347         quad_vertex_buffer.Bind();
 348         m_viewport_ubo.Bind();
 349
 350         glUniform4f(m_colour_uniform_location, 1.0f, 1.0f, 1.0f, 1.0f);
 351
 352         GLuint texID;
 353         glGenTextures(1, &texID);
 354         glBindTexture(GL_TEXTURE_2D, texID);
 355
 356         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 357         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 358         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
 359         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
 360
 361         glTexImage2D(GL_TEXTURE_2D, 0, bmp->format->BytesPerPixel, w, h, 0, texture_format, GL_UNSIGNED_BYTE, bmp->pixels);
 362
 363         glEnableVertexAttribArray(0);
 364         glEnableVertexAttribArray(1);
 365         glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 4*sizeof(float), (void*)(2*sizeof(float)));
 366         glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 4*sizeof(float), 0);
 367         glDisableVertexAttribArray(1);
 368         glDisableVertexAttribArray(0);
 369         glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
 370
 371         SDL_FreeSurface(bmp);
 372 }
 373
 374 void Screen::DebugFontInit(const char *name, float font_size)
 375 {
 376         unsigned char font_atlas_data[1024*1024];
 377         FILE *font_file = fopen(name, "rb");
 378         fseek(font_file, 0, SEEK_END);
 379         size_t font_file_size = ftell(font_file);
 380         fseek(font_file, 0, SEEK_SET);
 381         unsigned char *font_file_data = (unsigned char*)malloc(font_file_size);
 382         SDL_assert(fread(font_file_data, 1, font_file_size, font_file) == font_file_size);
 383         fclose(font_file);
 384         stbtt_BakeFontBitmap(font_file_data,0, font_size, font_atlas_data,1024,1024, 32,96, m_debug_font_rects);
 385         free(font_file_data);
 386         glGenTextures(1, &m_debug_font_atlas);
 387         glBindTexture(GL_TEXTURE_2D, m_debug_font_atlas);
 388         glTexImage2D(GL_TEXTURE_2D, 0, GL_RED, 1024,1024, 0, GL_RED, GL_UNSIGNED_BYTE, font_atlas_data);
 389         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 390         m_debug_font_size = font_size;
 391
 392         m_debug_font_vertices.SetUsage(GraphicsBuffer::BufferUsageStreamDraw);
 393         m_debug_font_vertices.SetType(GraphicsBuffer::BufferTypeVertex);
 394         m_debug_font_vertices.Upload(8192,NULL);
 395         m_debug_font_vertex_head = 0;
 396
 397         m_debug_font_indices.SetUsage(GraphicsBuffer::BufferUsageStreamDraw);
 398         m_debug_font_indices.SetType(GraphicsBuffer::BufferTypeIndex);
 399         m_debug_font_indices.Resize(500);
 400         m_debug_font_index_head = 0;
 401 }
 402
 403 void Screen::DebugFontClear()
 404 {
 405         m_debug_font_x = m_debug_font_y = 0;
 406         if (!m_debug_font_atlas) return;
 407         DebugFontPrint("\n");
 408 }
 409
 410 void Screen::DebugFontFlush()
 411 {
 412
 413
 414         glEnable(GL_BLEND);
 415         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 416         glBindTexture(GL_TEXTURE_2D, m_debug_font_atlas);
 417
 418         m_font_prog.Use();
 419         m_viewport_ubo.Bind();
 420         m_debug_font_vertices.Bind();
 421         m_debug_font_indices.Bind();
 422         glUniform4f(m_colour_uniform_location, 0,0,0,1);
 423         glEnableVertexAttribArray(0);
 424         glEnableVertexAttribArray(1);
 425         glEnable(GL_PRIMITIVE_RESTART);
 426         glPrimitiveRestartIndex(65535);
 427         glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 4*sizeof(float), 0);
 428         glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 4*sizeof(float), (void*)(2*sizeof(float)));
 429         glDrawElements(GL_TRIANGLE_STRIP, m_debug_font_index_head, GL_UNSIGNED_SHORT, 0);
 430         glDisable(GL_PRIMITIVE_RESTART);
 431         glDisableVertexAttribArray(1);
 432         glDisableVertexAttribArray(0);
 433
 434         glDisable(GL_BLEND);
 435
 436         m_debug_font_vertices.Invalidate();
 437         m_debug_font_indices.Invalidate();
 438         m_debug_font_vertex_head = 0;
 439         m_debug_font_index_head = 0;
 440 }
 441
 442 struct fontvertex
 443 {
 444         float x, y, s, t;
 445 };
 446
 447 void Screen::DebugFontPrint(const char* str)
 448 {
 449         if (!m_debug_font_atlas) return;
 450
 451
 452         BufferBuilder<fontvertex> vertexData(m_debug_font_vertices.MapRange(m_debug_font_vertex_head*sizeof(float), m_debug_font_vertices.GetSize() - m_debug_font_vertex_head*sizeof(float), false, true, true), m_debug_font_vertices.GetSize() - m_debug_font_vertex_head*sizeof(float));
 453         BufferBuilder<uint16_t> indexData(m_debug_font_indices.MapRange(m_debug_font_index_head*sizeof(uint16_t), m_debug_font_indices.GetSize() - m_debug_font_index_head*sizeof(uint16_t), false, true, true), m_debug_font_indices.GetSize() - m_debug_font_index_head*sizeof(uint16_t));
 454
 455         size_t baseVertex = m_debug_font_vertex_head/4;
 456         while (*str) {
 457                 if (!vertexData.Free(4) || !indexData.Free(5))
 458                 {
 459                         m_debug_font_indices.UnMap();
 460                         m_debug_font_vertices.UnMap();
 461                         DebugFontFlush();
 462                         DebugFontPrint(str);
 463                         return;
 464                 }
 465                 if (*str >= 32 && (unsigned char)(*str) < 128) {
 466                         stbtt_aligned_quad q;
 467                         stbtt_GetBakedQuad(m_debug_font_rects, 1024,1024, *str-32, &m_debug_font_x,&m_debug_font_y,&q,1);
 468                         size_t index = vertexData.Add({q.x0, q.y0, q.s0, q.t0});
 469                         index += baseVertex;
 470                         indexData.Add(index);
 471                         index = vertexData.Add({q.x1, q.y0, q.s1, q.t0});
 472                         index += baseVertex;
 473                         indexData.Add(index);
 474                         index = vertexData.Add({q.x0, q.y1, q.s0, q.t1});
 475                         index += baseVertex;
 476                         indexData.Add(index);
 477                         index = vertexData.Add({q.x1, q.y1, q.s1, q.t1});
 478                         index += baseVertex;
 479                         indexData.Add(index);
 480                         indexData.Add(65535);
 481
 482                         m_debug_font_vertex_head += 16;
 483                         m_debug_font_index_head += 5;
 484
 485                 }
 486                 else if (*str == '\n')
 487                 {
 488                         m_debug_font_x = 0;
 489                         m_debug_font_y += m_debug_font_size;
 490                 }
 491                 ++str;
 492         }
 493         m_debug_font_indices.UnMap();
 494         m_debug_font_vertices.UnMap();
 495         //DebugFontFlush();
 496 }
 497
 498 void Screen::DebugFontPrintF(const char *fmt, ...)
 499 {
 500         char buffer[BUFSIZ];
 501         va_list va;
 502         va_start(va, fmt);
 503         vsnprintf(buffer, BUFSIZ, fmt,va);
 504         va_end(va);
 505         DebugFontPrint(buffer);
 506 }