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