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