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 "shaderprogram.h"
   9
  10 #define BASICTEX_VERT \
  11         "#version 140\n"\
  12         "#extension GL_ARB_shading_language_420pack : require\n"\
  13         "#extension GL_ARB_explicit_attrib_location : require\n"\
  14         "\n"\
  15         "layout(std140, binding=0) uniform Viewport\n"\
  16         "{\n"\
  17         "\tfloat width;\n"\
  18         "\tfloat height;\n"\
  19         "};\n"\
  20         "\n"\
  21         "layout(location = 0) in vec2 position;\n"\
  22         "layout(location = 1) in vec2 tex_coord;\n"\
  23         "\n"\
  24         "out vec2 fp_tex_coord;\n"\
  25         "\n"\
  26         "void main()\n"\
  27         "{\n"\
  28         "\t// Transform to clip coordinates (-1,1, -1,1).\n"\
  29         "\tgl_Position.x = (position.x*2/width) - 1;\n"\
  30         "\tgl_Position.y = 1 - (position.y*2/height);\n"\
  31         "\tgl_Position.z = 0.0;\n"\
  32         "\tgl_Position.w = 1.0;\n"\
  33         "\tfp_tex_coord = tex_coord;\n"\
  34         "}\n"
  35
  36 #define BASICTEX_FRAG \
  37         "#version 140\n"\
  38         "\n"\
  39         "in vec2 fp_tex_coord;\n"\
  40         "\n"\
  41         "out vec4 output_colour;\n"\
  42         "\n"\
  43         "uniform sampler2D tex;\n"\
  44         "uniform vec4 colour;\n"\
  45         "\n"\
  46         "void main()\n"\
  47         "{\n"\
  48         "\toutput_colour = colour;\n"\
  49         "\toutput_colour.a = texture(tex, fp_tex_coord).r;\n"\
  50         "}\n"
  51
  52 using namespace IPDF;
  53 using namespace std;
  54
  55 static void opengl_debug_callback(GLenum source, GLenum type, GLuint id, GLenum severity, GLsizei length, const GLchar* msg, const void *data)
  56 {
  57         Error("OpenGL Error (%d): %s", id, msg);
  58 }
  59
  60
  61 Screen::Screen()
  62 {
  63         SDL_Init(SDL_INIT_VIDEO);
  64         m_window = SDL_CreateWindow("IPDF", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
  65                         800, 600, SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE);
  66
  67         if (!m_window)
  68         {
  69                 Fatal("Couldn't create window!");
  70         }
  71
  72         SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
  73         SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 1);
  74         SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, SDL_GL_CONTEXT_DEBUG_FLAG);
  75         SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
  76
  77         m_gl_context = SDL_GL_CreateContext(m_window);
  78
  79         ogl_LoadFunctions();
  80
  81         // Why is this so horribly broken?
  82         if (ogl_IsVersionGEQ(3,0))
  83         {
  84                 Fatal("We require OpenGL 3.1, but you have version %d.%d!",ogl_GetMajorVersion(), ogl_GetMinorVersion());
  85         }
  86
  87         if (!SDL_GL_ExtensionSupported("GL_ARB_shading_language_420pack"))
  88         {
  89                 Fatal("Your system does not support the ARB_shading_language_420pack extension, which is required.");
  90         }
  91
  92         if (!SDL_GL_ExtensionSupported("GL_ARB_explicit_attrib_location"))
  93         {
  94                 Fatal("Your system does not support the ARB_explicit_attrib_location extension, which is required.");
  95         }
  96
  97         glDebugMessageCallback(opengl_debug_callback, 0);
  98
  99         GLuint default_vao;
 100         glGenVertexArrays(1, &default_vao);
 101         glBindVertexArray(default_vao);
 102
 103         //TODO: Error checking.
 104         m_texture_prog.AttachVertexProgram(BASICTEX_VERT);
 105         m_texture_prog.AttachFragmentProgram(BASICTEX_FRAG);
 106         m_texture_prog.Link();
 107         m_texture_prog.Use();
 108
 109         // We always want to use the texture bound to texture unit 0.
 110         GLint texture_uniform_location = m_texture_prog.GetUniformLocation("tex");
 111         glUniform1i(texture_uniform_location, 0);
 112
 113         m_colour_uniform_location = m_texture_prog.GetUniformLocation("colour");
 114
 115         m_viewport_ubo.SetUsage(GraphicsBuffer::BufferUsageDynamicDraw);
 116         m_viewport_ubo.SetType(GraphicsBuffer::BufferTypeUniform);
 117
 118         m_debug_font_atlas = 0;
 119
 120         ResizeViewport(800, 600);
 121
 122         Clear();
 123         Present();
 124
 125
 126 }
 127
 128 Screen::~Screen()
 129 {
 130         SDL_GL_DeleteContext(m_gl_context);
 131         SDL_DestroyWindow(m_window);
 132         SDL_Quit();
 133 }
 134
 135 void Screen::Clear(float r, float g, float b, float a)
 136 {
 137         glClearColor(r,g,b,a);
 138         glClear(GL_COLOR_BUFFER_BIT);
 139         DebugFontClear();
 140 }
 141
 142 void Screen::ResizeViewport(int width, int height)
 143 {
 144         glViewport(0, 0, width, height);
 145         m_viewport_width = width;
 146         m_viewport_height = height;
 147         GLfloat viewportfloats[] = {(float)width, (float)height};
 148         m_viewport_ubo.Upload(sizeof(float)*2, viewportfloats);
 149 }
 150
 151 bool Screen::PumpEvents()
 152 {
 153         SDL_Event evt;
 154         bool no_quit_requested = true;
 155         while (SDL_PollEvent(&evt))
 156         {
 157                 switch (evt.type)
 158                 {
 159                 case SDL_QUIT:
 160                         no_quit_requested = false;
 161                         break;
 162                 case SDL_WINDOWEVENT:
 163                         switch (evt.window.event)
 164                         {
 165                         case SDL_WINDOWEVENT_RESIZED:
 166                         case SDL_WINDOWEVENT_SIZE_CHANGED:
 167                                 ResizeViewport(evt.window.data1, evt.window.data2);
 168                                 break;
 169                         }
 170                         break;
 171                 case SDL_MOUSEMOTION:
 172                         m_last_mouse_x = evt.motion.x;
 173                         m_last_mouse_y = evt.motion.y;
 174                         if (m_mouse_handler)
 175                         {
 176                                 m_mouse_handler(evt.motion.x, evt.motion.y,evt.motion.state, 0);
 177                         }
 178                         break;
 179                 case SDL_MOUSEBUTTONDOWN:
 180                 case SDL_MOUSEBUTTONUP:
 181                         m_last_mouse_x = evt.button.x;
 182                         m_last_mouse_y = evt.button.y;
 183                         if (m_mouse_handler)
 184                         {
 185                                 m_mouse_handler(evt.button.x, evt.button.y, evt.button.state?evt.button.button:0, 0);
 186                         }
 187                         break;
 188                 case SDL_MOUSEWHEEL:
 189                         if (m_mouse_handler)
 190                         {
 191                                 m_mouse_handler(m_last_mouse_x, m_last_mouse_y, 0, evt.wheel.y);
 192                         }
 193                         break;
 194                 case SDL_KEYDOWN:
 195                 {
 196                         Debug("Key %c down", (char)evt.key.keysym.sym);
 197                         if (isalnum((char)evt.key.keysym.sym))
 198                         {
 199                                 char filename[] = "0.bmp";
 200                                 filename[0] = (char)evt.key.keysym.sym;
 201                                 ScreenShot(filename);
 202                         }
 203                         break;
 204                 }
 205                 default:
 206                         break;
 207                 }
 208         }
 209         return no_quit_requested;
 210 }
 211
 212 void Screen::SetMouseCursor(Screen::MouseCursors cursor)
 213 {
 214         SDL_SystemCursor system_cursor_id = SDL_SYSTEM_CURSOR_ARROW;
 215         switch (cursor)
 216         {
 217         case CursorArrow: system_cursor_id = SDL_SYSTEM_CURSOR_ARROW; break;
 218         case CursorWait: system_cursor_id = SDL_SYSTEM_CURSOR_WAIT; break;
 219         case CursorWaitArrow: system_cursor_id = SDL_SYSTEM_CURSOR_WAITARROW; break;
 220         case CursorMove: system_cursor_id = SDL_SYSTEM_CURSOR_SIZEALL; break;
 221         case CursorHand: system_cursor_id = SDL_SYSTEM_CURSOR_HAND; break;
 222         default: break;
 223         }
 224         SDL_Cursor *system_cursor = SDL_CreateSystemCursor(system_cursor_id);
 225         SDL_SetCursor(system_cursor);
 226         //TODO: Check if we need to free the system cursors.
 227 }
 228
 229 void Screen::Present()
 230 {
 231         if (m_debug_font_atlas)
 232                 DebugFontFlush();
 233         SDL_GL_SwapWindow(m_window);
 234 }
 235
 236 void Screen::ScreenShot(const char * filename) const
 237 {
 238         Debug("Attempting to save BMP to file %s", filename);
 239
 240         int w = ViewportWidth();
 241         int h = ViewportHeight();
 242         unsigned char * pixels = new unsigned char[w*h*4];
 243         if (pixels == NULL)
 244                 Fatal("Failed to allocate %d x %d x 4 = %d pixel array", w, h, w*h*4);
 245
 246         for (int y = 0; y < h; ++y)
 247         {
 248                 glReadPixels(0,h-y-1,w, 1, GL_RGBA, GL_UNSIGNED_BYTE, &pixels[y*w*4]);
 249         }
 250
 251 #if SDL_BYTEORDER == SDL_LIL_ENDIAN
 252         SDL_Surface * surf = SDL_CreateRGBSurfaceFrom(pixels, w, h, 8*4, w*4, 0x000000ff,0x0000ff00,0x00ff0000,0xff000000);
 253 #else
 254         SDL_Surface * surf = SDL_CreateRGBSurfaceFrom(pixels, w, h, 8*4, w*4, 0xff000000,0x00ff0000,0x0000ff00,0x000000ff);
 255 #endif
 256         if (surf == NULL)
 257                 Fatal("Failed to create SDL_Surface from pixel data - %s", SDL_GetError());
 258
 259         GLenum texture_format = (surf->format->Rmask == 0x000000FF) ? GL_RGBA : GL_BGRA;
 260         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);
 261
 262         if (SDL_SaveBMP(surf, filename) != 0)
 263                 Fatal("SDL_SaveBMP failed - %s", SDL_GetError());
 264
 265         SDL_FreeSurface(surf);
 266         delete [] pixels;
 267         Debug("Succeeded!");
 268 }
 269
 270 /**
 271  * Render a BMP
 272  * NOT PART OF THE DOCUMENT FORMAT
 273  */
 274 void Screen::RenderBMP(const char * filename) const
 275 {
 276         if (access(filename, R_OK) == -1)
 277         {
 278                 Error("No such file \"%s\" - Nothing to render - You might have done this deliberately?", filename);
 279                 return;
 280         }
 281         SDL_Surface * bmp = SDL_LoadBMP(filename);
 282         if (bmp == NULL)
 283                 Fatal("Failed to load BMP from %s - %s", filename, SDL_GetError());
 284
 285         int w = bmp->w;
 286         int h = bmp->h;
 287
 288         GLenum texture_format;
 289         switch (bmp->format->BytesPerPixel)
 290         {
 291                 case 4: //contains alpha
 292                         texture_format = (bmp->format->Rmask == 0x000000FF) ? GL_RGBA : GL_BGRA;
 293                         break;
 294                 case 3: //does not contain alpha
 295                         texture_format = (bmp->format->Rmask == 0x000000FF) ? GL_RGB : GL_BGR;
 296                         break;
 297                 default:
 298                         Fatal("Could not understand SDL_Surface format (%d colours)", bmp->format->BytesPerPixel);
 299                         break;
 300         }
 301
 302         //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);
 303
 304         m_texture_prog.Use();
 305         GraphicsBuffer quad_vertex_buffer;
 306         quad_vertex_buffer.SetUsage(GraphicsBuffer::BufferUsageStaticDraw);
 307         quad_vertex_buffer.SetType(GraphicsBuffer::BufferTypeVertex);
 308         GLfloat quad[] = {
 309                 0, 0, 0, 0,
 310                 1, 0, ViewportWidth(), 0,
 311                 1, 1, ViewportWidth(), ViewportHeight(),
 312                 0, 1, 0, ViewportHeight()
 313         };
 314         quad_vertex_buffer.Upload(sizeof(GLfloat) * 16, quad);
 315         quad_vertex_buffer.Bind();
 316         m_viewport_ubo.Bind();
 317
 318         glUniform4f(m_colour_uniform_location, 1.0f, 1.0f, 1.0f, 1.0f);
 319
 320         GLuint texID;
 321         glGenTextures(1, &texID);
 322         glBindTexture(GL_TEXTURE_2D, texID);
 323
 324         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 325         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 326         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
 327         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
 328
 329         glTexImage2D(GL_TEXTURE_2D, 0, bmp->format->BytesPerPixel, w, h, 0, texture_format, GL_UNSIGNED_BYTE, bmp->pixels);
 330
 331         glEnableVertexAttribArray(0);
 332         glEnableVertexAttribArray(1);
 333         glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 4*sizeof(float), (void*)(2*sizeof(float)));
 334         glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 4*sizeof(float), 0);
 335         glDisableVertexAttribArray(1);
 336         glDisableVertexAttribArray(0);
 337         glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
 338
 339         SDL_FreeSurface(bmp);
 340 }
 341
 342 void Screen::DebugFontInit(const char *name, float font_size)
 343 {
 344         unsigned char font_atlas_data[1024*1024];
 345         FILE *font_file = fopen(name, "rb");
 346         fseek(font_file, 0, SEEK_END);
 347         size_t font_file_size = ftell(font_file);
 348         fseek(font_file, 0, SEEK_SET);
 349         unsigned char *font_file_data = (unsigned char*)malloc(font_file_size);
 350         fread(font_file_data, 1, font_file_size, font_file);
 351         fclose(font_file);
 352         stbtt_BakeFontBitmap(font_file_data,0, font_size, font_atlas_data,1024,1024, 32,96, m_debug_font_rects);
 353         free(font_file_data);
 354         glGenTextures(1, &m_debug_font_atlas);
 355         glBindTexture(GL_TEXTURE_2D, m_debug_font_atlas);
 356         glTexImage2D(GL_TEXTURE_2D, 0, GL_RED, 1024,1024, 0, GL_RED, GL_UNSIGNED_BYTE, font_atlas_data);
 357         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 358         m_debug_font_size = font_size;
 359
 360         m_debug_font_vertices.SetUsage(GraphicsBuffer::BufferUsageStreamDraw);
 361         m_debug_font_vertices.SetType(GraphicsBuffer::BufferTypeVertex);
 362         m_debug_font_vertices.Upload(8192, nullptr);
 363         m_debug_font_vertex_head = 0;
 364
 365         m_debug_font_indices.SetUsage(GraphicsBuffer::BufferUsageStreamDraw);
 366         m_debug_font_indices.SetType(GraphicsBuffer::BufferTypeIndex);
 367         m_debug_font_indices.Resize(500);
 368         m_debug_font_index_head = 0;
 369 }
 370
 371 void Screen::DebugFontClear()
 372 {
 373         m_debug_font_x = m_debug_font_y = 0;
 374         if (!m_debug_font_atlas) return;
 375         DebugFontPrint("\n");
 376 }
 377
 378 void Screen::DebugFontFlush()
 379 {
 380
 381
 382         glEnable(GL_BLEND);
 383         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 384         glBindTexture(GL_TEXTURE_2D, m_debug_font_atlas);
 385
 386         m_texture_prog.Use();
 387         m_viewport_ubo.Bind();
 388         m_debug_font_vertices.Bind();
 389         m_debug_font_indices.Bind();
 390         glUniform4f(m_colour_uniform_location, 0,0,0,1);
 391         glEnableVertexAttribArray(0);
 392         glEnableVertexAttribArray(1);
 393         glEnable(GL_PRIMITIVE_RESTART);
 394         glPrimitiveRestartIndex(65535);
 395         glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 4*sizeof(float), (void*)(2*sizeof(float)));
 396         glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 4*sizeof(float), 0);
 397         glDrawElements(GL_TRIANGLE_STRIP, m_debug_font_index_head, GL_UNSIGNED_SHORT, 0);
 398         glDisable(GL_PRIMITIVE_RESTART);
 399         glDisableVertexAttribArray(1);
 400         glDisableVertexAttribArray(0);
 401
 402         glDisable(GL_BLEND);
 403
 404         m_debug_font_vertex_head = 0;
 405         m_debug_font_index_head = 0;
 406 }
 407
 408 void Screen::DebugFontPrint(const char* str)
 409 {
 410         if (!m_debug_font_atlas) return;
 411
 412         float *vertexData = (float*)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);
 413         uint16_t *indexData = (uint16_t*)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);
 414         while (*str) {
 415                 if ((m_debug_font_vertex_head*sizeof(float) + 16*sizeof(float) >= m_debug_font_vertices.GetSize() ) ||
 416                         (m_debug_font_index_head*sizeof(uint16_t) + 5*sizeof(uint16_t) >= m_debug_font_indices.GetSize()))
 417                 {
 418                         m_debug_font_indices.UnMap();
 419                         m_debug_font_vertices.UnMap();
 420                         DebugFontFlush();
 421                         DebugFontPrint(str);
 422                         return;
 423                 }
 424                 if (*str >= 32 && *str < 128) {
 425                         stbtt_aligned_quad q;
 426                         stbtt_GetBakedQuad(m_debug_font_rects, 1024,1024, *str-32, &m_debug_font_x,&m_debug_font_y,&q,1);
 427                         *vertexData = q.s0; vertexData++;
 428                         *vertexData = q.t0; vertexData++;
 429                         *vertexData = q.x0; vertexData++;
 430                         *vertexData = q.y0; vertexData++;
 431                         *vertexData = q.s1; vertexData++;
 432                         *vertexData = q.t0; vertexData++;
 433                         *vertexData = q.x1; vertexData++;
 434                         *vertexData = q.y0; vertexData++;
 435                         *vertexData = q.s1; vertexData++;
 436                         *vertexData = q.t1; vertexData++;
 437                         *vertexData = q.x1; vertexData++;
 438                         *vertexData = q.y1; vertexData++;
 439                         *vertexData = q.s0; vertexData++;
 440                         *vertexData = q.t1; vertexData++;
 441                         *vertexData = q.x0; vertexData++;
 442                         *vertexData = q.y1; vertexData++;
 443
 444                         *indexData = m_debug_font_vertex_head/4; indexData++;
 445                         *indexData = m_debug_font_vertex_head/4+1; indexData++;
 446                         *indexData = m_debug_font_vertex_head/4+3; indexData++;
 447                         *indexData = m_debug_font_vertex_head/4+2; indexData++;
 448                         *indexData = 65535; indexData++;
 449
 450                         m_debug_font_vertex_head += 16;
 451                         m_debug_font_index_head += 5;
 452
 453                 }
 454                 else if (*str == '\n')
 455                 {
 456                         m_debug_font_x = 0;
 457                         m_debug_font_y += m_debug_font_size;
 458                 }
 459                 ++str;
 460         }
 461         m_debug_font_indices.UnMap();
 462         m_debug_font_vertices.UnMap();
 463         //DebugFontFlush();
 464 }
 465
 466 void Screen::DebugFontPrintF(const char *fmt, ...)
 467 {
 468         char buffer[BUFSIZ];
 469         va_list va;
 470         va_start(va, fmt);
 471         vsnprintf(buffer, BUFSIZ, fmt,va);
 472         va_end(va);
 473         DebugFontPrint(buffer);
 474 }