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 \
  12         "#version 140\n"\
  13         "#extension GL_ARB_shading_language_420pack : require\n"\
  14         "#extension GL_ARB_explicit_attrib_location : require\n"\
  15         "\n"\
  16         "layout(std140, binding=0) uniform Viewport\n"\
  17         "{\n"\
  18         "\tfloat width;\n"\
  19         "\tfloat height;\n"\
  20         "};\n"\
  21         "\n"\
  22         "layout(location = 0) in vec2 position;\n"\
  23         "layout(location = 1) in vec2 tex_coord;\n"\
  24         "\n"\
  25         "out vec2 fp_tex_coord;\n"\
  26         "\n"\
  27         "void main()\n"\
  28         "{\n"\
  29         "\t// Transform to clip coordinates (-1,1, -1,1).\n"\
  30         "\tgl_Position.x = (position.x*2/width) - 1;\n"\
  31         "\tgl_Position.y = 1 - (position.y*2/height);\n"\
  32         "\tgl_Position.z = 0.0;\n"\
  33         "\tgl_Position.w = 1.0;\n"\
  34         "\tfp_tex_coord = tex_coord;\n"\
  35         "}\n"
  36
  37 #define BASICTEX_FRAG \
  38         "#version 140\n"\
  39         "\n"\
  40         "in vec2 fp_tex_coord;\n"\
  41         "\n"\
  42         "out vec4 output_colour;\n"\
  43         "\n"\
  44         "uniform sampler2D tex;\n"\
  45         "uniform vec4 colour;\n"\
  46         "\n"\
  47         "void main()\n"\
  48         "{\n"\
  49         "\toutput_colour = colour;\n"\
  50         "\toutput_colour.a = texture(tex, fp_tex_coord).r;\n"\
  51         "}\n"
  52
  53 using namespace IPDF;
  54 using namespace std;
  55
  56 static void opengl_debug_callback(GLenum source, GLenum type, GLuint id, GLenum severity, GLsizei length, const GLchar* msg, const void *data)
  57 {
  58         Error("OpenGL Error (%d): %s", id, msg);
  59 }
  60
  61
  62 Screen::Screen()
  63 {
  64         SDL_Init(SDL_INIT_VIDEO);
  65         m_window = SDL_CreateWindow("IPDF", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
  66                         800, 600, SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE);
  67
  68         if (!m_window)
  69         {
  70                 Fatal("Couldn't create window!");
  71         }
  72
  73         SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
  74         SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 1);
  75         SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, SDL_GL_CONTEXT_DEBUG_FLAG);
  76         SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
  77
  78         m_gl_context = SDL_GL_CreateContext(m_window);
  79
  80         ogl_LoadFunctions();
  81
  82         // Why is this so horribly broken?
  83         if (ogl_IsVersionGEQ(3,0))
  84         {
  85                 Fatal("We require OpenGL 3.1, but you have version %d.%d!",ogl_GetMajorVersion(), ogl_GetMinorVersion());
  86         }
  87
  88         if (!SDL_GL_ExtensionSupported("GL_ARB_shading_language_420pack"))
  89         {
  90                 Fatal("Your system does not support the ARB_shading_language_420pack extension, which is required.");
  91         }
  92
  93         if (!SDL_GL_ExtensionSupported("GL_ARB_explicit_attrib_location"))
  94         {
  95                 Fatal("Your system does not support the ARB_explicit_attrib_location extension, which is required.");
  96         }
  97
  98         m_frame_begin_time = SDL_GetPerformanceCounter();
  99         m_last_frame_time = 0;
 100         m_last_frame_gpu_timer = 0;
 101         glGenQueries(1, &m_frame_gpu_timer);
 102         glBeginQuery(GL_TIME_ELAPSED, m_frame_gpu_timer);
 103
 104         glDebugMessageCallback(opengl_debug_callback, 0);
 105
 106         GLuint default_vao;
 107         glGenVertexArrays(1, &default_vao);
 108         glBindVertexArray(default_vao);
 109
 110         //TODO: Error checking.
 111         m_texture_prog.AttachVertexProgram(BASICTEX_VERT);
 112         m_texture_prog.AttachFragmentProgram(BASICTEX_FRAG);
 113         m_texture_prog.Link();
 114         m_texture_prog.Use();
 115
 116         // We always want to use the texture bound to texture unit 0.
 117         GLint texture_uniform_location = m_texture_prog.GetUniformLocation("tex");
 118         glUniform1i(texture_uniform_location, 0);
 119
 120         m_colour_uniform_location = m_texture_prog.GetUniformLocation("colour");
 121
 122         m_viewport_ubo.SetUsage(GraphicsBuffer::BufferUsageDynamicDraw);
 123         m_viewport_ubo.SetType(GraphicsBuffer::BufferTypeUniform);
 124
 125         m_debug_font_atlas = 0;
 126
 127         ResizeViewport(800, 600);
 128
 129         Clear();
 130         Present();
 131
 132
 133 }
 134
 135 Screen::~Screen()
 136 {
 137         SDL_GL_DeleteContext(m_gl_context);
 138         SDL_DestroyWindow(m_window);
 139         SDL_Quit();
 140 }
 141
 142 void Screen::Clear(float r, float g, float b, float a)
 143 {
 144         glClearColor(r,g,b,a);
 145         glClear(GL_COLOR_BUFFER_BIT);
 146         DebugFontClear();
 147 }
 148
 149 void Screen::ResizeViewport(int width, int height)
 150 {
 151         glViewport(0, 0, width, height);
 152         m_viewport_width = width;
 153         m_viewport_height = height;
 154         GLfloat viewportfloats[] = {(float)width, (float)height};
 155         m_viewport_ubo.Upload(sizeof(float)*2, viewportfloats);
 156 }
 157
 158 bool Screen::PumpEvents()
 159 {
 160         SDL_Event evt;
 161         bool no_quit_requested = true;
 162         while (SDL_PollEvent(&evt))
 163         {
 164                 switch (evt.type)
 165                 {
 166                 case SDL_QUIT:
 167                         no_quit_requested = false;
 168                         break;
 169                 case SDL_WINDOWEVENT:
 170                         switch (evt.window.event)
 171                         {
 172                         case SDL_WINDOWEVENT_RESIZED:
 173                         case SDL_WINDOWEVENT_SIZE_CHANGED:
 174                                 ResizeViewport(evt.window.data1, evt.window.data2);
 175                                 break;
 176                         }
 177                         break;
 178                 case SDL_MOUSEMOTION:
 179                         m_last_mouse_x = evt.motion.x;
 180                         m_last_mouse_y = evt.motion.y;
 181                         if (m_mouse_handler)
 182                         {
 183                                 m_mouse_handler(evt.motion.x, evt.motion.y,evt.motion.state, 0);
 184                         }
 185                         break;
 186                 case SDL_MOUSEBUTTONDOWN:
 187                 case SDL_MOUSEBUTTONUP:
 188                         m_last_mouse_x = evt.button.x;
 189                         m_last_mouse_y = evt.button.y;
 190                         if (m_mouse_handler)
 191                         {
 192                                 m_mouse_handler(evt.button.x, evt.button.y, evt.button.state?evt.button.button:0, 0);
 193                         }
 194                         break;
 195                 case SDL_MOUSEWHEEL:
 196                         if (m_mouse_handler)
 197                         {
 198                                 m_mouse_handler(m_last_mouse_x, m_last_mouse_y, 0, evt.wheel.y);
 199                         }
 200                         break;
 201                 case SDL_KEYDOWN:
 202                 {
 203                         Debug("Key %c down", (char)evt.key.keysym.sym);
 204                         if (isalnum((char)evt.key.keysym.sym))
 205                         {
 206                                 char filename[] = "0.bmp";
 207                                 filename[0] = (char)evt.key.keysym.sym;
 208                                 ScreenShot(filename);
 209                         }
 210                         break;
 211                 }
 212                 default:
 213                         break;
 214                 }
 215         }
 216         return no_quit_requested;
 217 }
 218
 219 void Screen::SetMouseCursor(Screen::MouseCursors cursor)
 220 {
 221         SDL_SystemCursor system_cursor_id = SDL_SYSTEM_CURSOR_ARROW;
 222         switch (cursor)
 223         {
 224         case CursorArrow: system_cursor_id = SDL_SYSTEM_CURSOR_ARROW; break;
 225         case CursorWait: system_cursor_id = SDL_SYSTEM_CURSOR_WAIT; break;
 226         case CursorWaitArrow: system_cursor_id = SDL_SYSTEM_CURSOR_WAITARROW; break;
 227         case CursorMove: system_cursor_id = SDL_SYSTEM_CURSOR_SIZEALL; break;
 228         case CursorHand: system_cursor_id = SDL_SYSTEM_CURSOR_HAND; break;
 229         default: break;
 230         }
 231         SDL_Cursor *system_cursor = SDL_CreateSystemCursor(system_cursor_id);
 232         SDL_SetCursor(system_cursor);
 233         //TODO: Check if we need to free the system cursors.
 234 }
 235
 236 void Screen::Present()
 237 {
 238         if (m_debug_font_atlas)
 239                 DebugFontFlush();
 240         m_last_frame_time = SDL_GetPerformanceCounter() - m_frame_begin_time;
 241         glEndQuery(GL_TIME_ELAPSED);
 242         SDL_GL_SwapWindow(m_window);
 243         m_frame_begin_time = SDL_GetPerformanceCounter();
 244         if (m_last_frame_gpu_timer)
 245                 glDeleteQueries(1, &m_last_frame_gpu_timer);
 246         m_last_frame_gpu_timer = m_frame_gpu_timer;
 247         glGenQueries(1, &m_frame_gpu_timer);
 248         glBeginQuery(GL_TIME_ELAPSED, m_frame_gpu_timer);
 249 }
 250
 251 double Screen::GetLastFrameTimeGPU() const
 252 {
 253         if (!m_last_frame_gpu_timer)
 254                 return 0;
 255         uint64_t frame_time_ns;
 256         glGetQueryObjectui64v(m_last_frame_gpu_timer, GL_QUERY_RESULT, &frame_time_ns);
 257         return frame_time_ns/1000000000.0;
 258 }
 259
 260 void Screen::ScreenShot(const char * filename) const
 261 {
 262         Debug("Attempting to save BMP to file %s", filename);
 263
 264         int w = ViewportWidth();
 265         int h = ViewportHeight();
 266         unsigned char * pixels = new unsigned char[w*h*4];
 267         if (pixels == NULL)
 268                 Fatal("Failed to allocate %d x %d x 4 = %d pixel array", w, h, w*h*4);
 269
 270         for (int y = 0; y < h; ++y)
 271         {
 272                 glReadPixels(0,h-y-1,w, 1, GL_RGBA, GL_UNSIGNED_BYTE, &pixels[y*w*4]);
 273         }
 274
 275 #if SDL_BYTEORDER == SDL_LIL_ENDIAN
 276         SDL_Surface * surf = SDL_CreateRGBSurfaceFrom(pixels, w, h, 8*4, w*4, 0x000000ff,0x0000ff00,0x00ff0000,0xff000000);
 277 #else
 278         SDL_Surface * surf = SDL_CreateRGBSurfaceFrom(pixels, w, h, 8*4, w*4, 0xff000000,0x00ff0000,0x0000ff00,0x000000ff);
 279 #endif
 280         if (surf == NULL)
 281                 Fatal("Failed to create SDL_Surface from pixel data - %s", SDL_GetError());
 282
 283         GLenum texture_format = (surf->format->Rmask == 0x000000FF) ? GL_RGBA : GL_BGRA;
 284         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);
 285
 286         if (SDL_SaveBMP(surf, filename) != 0)
 287                 Fatal("SDL_SaveBMP failed - %s", SDL_GetError());
 288
 289         SDL_FreeSurface(surf);
 290         delete [] pixels;
 291         Debug("Succeeded!");
 292 }
 293
 294 /**
 295  * Render a BMP
 296  * NOT PART OF THE DOCUMENT FORMAT
 297  */
 298 void Screen::RenderBMP(const char * filename) const
 299 {
 300         if (access(filename, R_OK) == -1)
 301         {
 302                 Error("No such file \"%s\" - Nothing to render - You might have done this deliberately?", filename);
 303                 return;
 304         }
 305         SDL_Surface * bmp = SDL_LoadBMP(filename);
 306         if (bmp == NULL)
 307                 Fatal("Failed to load BMP from %s - %s", filename, SDL_GetError());
 308
 309         int w = bmp->w;
 310         int h = bmp->h;
 311
 312         GLenum texture_format;
 313         switch (bmp->format->BytesPerPixel)
 314         {
 315                 case 4: //contains alpha
 316                         texture_format = (bmp->format->Rmask == 0x000000FF) ? GL_RGBA : GL_BGRA;
 317                         break;
 318                 case 3: //does not contain alpha
 319                         texture_format = (bmp->format->Rmask == 0x000000FF) ? GL_RGB : GL_BGR;
 320                         break;
 321                 default:
 322                         Fatal("Could not understand SDL_Surface format (%d colours)", bmp->format->BytesPerPixel);
 323                         break;
 324         }
 325
 326         //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);
 327
 328         m_texture_prog.Use();
 329         GraphicsBuffer quad_vertex_buffer;
 330         quad_vertex_buffer.SetUsage(GraphicsBuffer::BufferUsageStaticDraw);
 331         quad_vertex_buffer.SetType(GraphicsBuffer::BufferTypeVertex);
 332         GLfloat quad[] = {
 333                 0, 0, 0, 0,
 334                 1, 0, (float)ViewportWidth(), 0,
 335                 1, 1, (float)ViewportWidth(), (float)ViewportHeight(),
 336                 0, 1, 0, (float)ViewportHeight()
 337         };
 338         quad_vertex_buffer.Upload(sizeof(GLfloat) * 16, quad);
 339         quad_vertex_buffer.Bind();
 340         m_viewport_ubo.Bind();
 341
 342         glUniform4f(m_colour_uniform_location, 1.0f, 1.0f, 1.0f, 1.0f);
 343
 344         GLuint texID;
 345         glGenTextures(1, &texID);
 346         glBindTexture(GL_TEXTURE_2D, texID);
 347
 348         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 349         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 350         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
 351         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
 352
 353         glTexImage2D(GL_TEXTURE_2D, 0, bmp->format->BytesPerPixel, w, h, 0, texture_format, GL_UNSIGNED_BYTE, bmp->pixels);
 354
 355         glEnableVertexAttribArray(0);
 356         glEnableVertexAttribArray(1);
 357         glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 4*sizeof(float), (void*)(2*sizeof(float)));
 358         glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 4*sizeof(float), 0);
 359         glDisableVertexAttribArray(1);
 360         glDisableVertexAttribArray(0);
 361         glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
 362
 363         SDL_FreeSurface(bmp);
 364 }
 365
 366 void Screen::DebugFontInit(const char *name, float font_size)
 367 {
 368         unsigned char font_atlas_data[1024*1024];
 369         FILE *font_file = fopen(name, "rb");
 370         fseek(font_file, 0, SEEK_END);
 371         size_t font_file_size = ftell(font_file);
 372         fseek(font_file, 0, SEEK_SET);
 373         unsigned char *font_file_data = (unsigned char*)malloc(font_file_size);
 374         fread(font_file_data, 1, font_file_size, font_file);
 375         fclose(font_file);
 376         stbtt_BakeFontBitmap(font_file_data,0, font_size, font_atlas_data,1024,1024, 32,96, m_debug_font_rects);
 377         free(font_file_data);
 378         glGenTextures(1, &m_debug_font_atlas);
 379         glBindTexture(GL_TEXTURE_2D, m_debug_font_atlas);
 380         glTexImage2D(GL_TEXTURE_2D, 0, GL_RED, 1024,1024, 0, GL_RED, GL_UNSIGNED_BYTE, font_atlas_data);
 381         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 382         m_debug_font_size = font_size;
 383
 384         m_debug_font_vertices.SetUsage(GraphicsBuffer::BufferUsageStreamDraw);
 385         m_debug_font_vertices.SetType(GraphicsBuffer::BufferTypeVertex);
 386         m_debug_font_vertices.Upload(8192, nullptr);
 387         m_debug_font_vertex_head = 0;
 388
 389         m_debug_font_indices.SetUsage(GraphicsBuffer::BufferUsageStreamDraw);
 390         m_debug_font_indices.SetType(GraphicsBuffer::BufferTypeIndex);
 391         m_debug_font_indices.Resize(500);
 392         m_debug_font_index_head = 0;
 393 }
 394
 395 void Screen::DebugFontClear()
 396 {
 397         m_debug_font_x = m_debug_font_y = 0;
 398         if (!m_debug_font_atlas) return;
 399         DebugFontPrint("\n");
 400 }
 401
 402 void Screen::DebugFontFlush()
 403 {
 404
 405
 406         glEnable(GL_BLEND);
 407         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 408         glBindTexture(GL_TEXTURE_2D, m_debug_font_atlas);
 409
 410         m_texture_prog.Use();
 411         m_viewport_ubo.Bind();
 412         m_debug_font_vertices.Bind();
 413         m_debug_font_indices.Bind();
 414         glUniform4f(m_colour_uniform_location, 0,0,0,1);
 415         glEnableVertexAttribArray(0);
 416         glEnableVertexAttribArray(1);
 417         glEnable(GL_PRIMITIVE_RESTART);
 418         glPrimitiveRestartIndex(65535);
 419         glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 4*sizeof(float), 0);
 420         glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 4*sizeof(float), (void*)(2*sizeof(float)));
 421         glDrawElements(GL_TRIANGLE_STRIP, m_debug_font_index_head, GL_UNSIGNED_SHORT, 0);
 422         glDisable(GL_PRIMITIVE_RESTART);
 423         glDisableVertexAttribArray(1);
 424         glDisableVertexAttribArray(0);
 425
 426         glDisable(GL_BLEND);
 427
 428         m_debug_font_vertex_head = 0;
 429         m_debug_font_index_head = 0;
 430 }
 431
 432 void Screen::DebugFontPrint(const char* str)
 433 {
 434         if (!m_debug_font_atlas) return;
 435
 436         struct fontvertex
 437         {
 438                 float x, y, s, t;
 439         };
 440
 441         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));
 442         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));
 443
 444         size_t baseVertex = m_debug_font_vertex_head/4;
 445         while (*str) {
 446                 if (!vertexData.Free(4) || !indexData.Free(5))
 447                 {
 448                         m_debug_font_indices.UnMap();
 449                         m_debug_font_vertices.UnMap();
 450                         DebugFontFlush();
 451                         DebugFontPrint(str);
 452                         return;
 453                 }
 454                 if (*str >= 32 && *str < 128) {
 455                         stbtt_aligned_quad q;
 456                         stbtt_GetBakedQuad(m_debug_font_rects, 1024,1024, *str-32, &m_debug_font_x,&m_debug_font_y,&q,1);
 457                         size_t index = vertexData.Add({q.x0, q.y0, q.s0, q.t0});
 458                         index += baseVertex;
 459                         indexData.Add(index);
 460                         index = vertexData.Add({q.x1, q.y0, q.s1, q.t0});
 461                         index += baseVertex;
 462                         indexData.Add(index);
 463                         index = vertexData.Add({q.x0, q.y1, q.s0, q.t1});
 464                         index += baseVertex;
 465                         indexData.Add(index);
 466                         index = vertexData.Add({q.x1, q.y1, q.s1, q.t1});
 467                         index += baseVertex;
 468                         indexData.Add(index);
 469                         indexData.Add(65535);
 470
 471                         m_debug_font_vertex_head += 16;
 472                         m_debug_font_index_head += 5;
 473
 474                 }
 475                 else if (*str == '\n')
 476                 {
 477                         m_debug_font_x = 0;
 478                         m_debug_font_y += m_debug_font_size;
 479                 }
 480                 ++str;
 481         }
 482         m_debug_font_indices.UnMap();
 483         m_debug_font_vertices.UnMap();
 484         //DebugFontFlush();
 485 }
 486
 487 void Screen::DebugFontPrintF(const char *fmt, ...)
 488 {
 489         char buffer[BUFSIZ];
 490         va_list va;
 491         va_start(va, fmt);
 492         vsnprintf(buffer, BUFSIZ, fmt,va);
 493         va_end(va);
 494         DebugFontPrint(buffer);
 495 }