src/video/sdl2_default_v.cpp

   1 /*
   2  * This file is part of OpenTTD.
   3  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
   4  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   5  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
   6  */
   7
   8 /** @file sdl2_default_v.cpp Implementation of the default backend for SDL2 video driver. */
   9
  10 #include "../stdafx.h"
  11 #include "../openttd.h"
  12 #include "../gfx_func.h"
  13 #include "../rev.h"
  14 #include "../blitter/factory.hpp"
  15 #include "../network/network.h"
  16 #include "../thread.h"
  17 #include "../progress.h"
  18 #include "../core/random_func.hpp"
  19 #include "../core/math_func.hpp"
  20 #include "../core/mem_func.hpp"
  21 #include "../core/geometry_func.hpp"
  22 #include "../fileio_func.h"
  23 #include "../framerate_type.h"
  24 #include "../window_func.h"
  25 #include "sdl2_default_v.h"
  26 #include <SDL.h>
  27 #include <mutex>
  28 #include <condition_variable>
  29 #ifdef __EMSCRIPTEN__
  30 #       include <emscripten.h>
  31 #       include <emscripten/html5.h>
  32 #endif
  33
  34 #include "../safeguards.h"
  35
  36 static FVideoDriver_SDL_Default iFVideoDriver_SDL_Default;
  37
  38 static SDL_Surface *_sdl_surface;
  39 static SDL_Surface *_sdl_rgb_surface;
  40 static SDL_Surface *_sdl_real_surface;
  41 static SDL_Palette *_sdl_palette;
  42
  43 void VideoDriver_SDL_Default::UpdatePalette()
  44 {
  45         SDL_Color pal[256];
  46
  47         for (int i = 0; i != this->local_palette.count_dirty; i++) {
  48                 pal[i].r = this->local_palette.palette[this->local_palette.first_dirty + i].r;
  49                 pal[i].g = this->local_palette.palette[this->local_palette.first_dirty + i].g;
  50                 pal[i].b = this->local_palette.palette[this->local_palette.first_dirty + i].b;
  51                 pal[i].a = 0;
  52         }
  53
  54         SDL_SetPaletteColors(_sdl_palette, pal, this->local_palette.first_dirty, this->local_palette.count_dirty);
  55         SDL_SetSurfacePalette(_sdl_surface, _sdl_palette);
  56 }
  57
  58 void VideoDriver_SDL_Default::MakePalette()
  59 {
  60         if (_sdl_palette == nullptr) {
  61                 _sdl_palette = SDL_AllocPalette(256);
  62                 if (_sdl_palette == nullptr) usererror("SDL2: Couldn't allocate palette: %s", SDL_GetError());
  63         }
  64
  65         CopyPalette(this->local_palette, true);
  66         this->UpdatePalette();
  67
  68         if (_sdl_surface != _sdl_real_surface) {
  69                 /* When using a shadow surface, also set our palette on the real screen. This lets SDL
  70                  * allocate as many colors (or approximations) as
  71                  * possible, instead of using only the default SDL
  72                  * palette. This allows us to get more colors exactly
  73                  * right and might allow using better approximations for
  74                  * other colors.
  75                  *
  76                  * Note that colors allocations are tried in-order, so
  77                  * this favors colors further up into the palette. Also
  78                  * note that if two colors from the same animation
  79                  * sequence are approximated using the same color, that
  80                  * animation will stop working.
  81                  *
  82                  * Since changing the system palette causes the colours
  83                  * to change right away, and allocations might
  84                  * drastically change, we can't use this for animation,
  85                  * since that could cause weird coloring between the
  86                  * palette change and the blitting below, so we only set
  87                  * the real palette during initialisation.
  88                  */
  89                 SDL_SetSurfacePalette(_sdl_real_surface, _sdl_palette);
  90         }
  91 }
  92
  93 void VideoDriver_SDL_Default::Paint()
  94 {
  95         PerformanceMeasurer framerate(PFE_VIDEO);
  96
  97         if (IsEmptyRect(this->dirty_rect) && this->local_palette.count_dirty == 0) return;
  98
  99         if (this->local_palette.count_dirty != 0) {
 100                 Blitter *blitter = BlitterFactory::GetCurrentBlitter();
 101
 102                 switch (blitter->UsePaletteAnimation()) {
 103                         case Blitter::PALETTE_ANIMATION_VIDEO_BACKEND:
 104                                 this->UpdatePalette();
 105                                 break;
 106
 107                         case Blitter::PALETTE_ANIMATION_BLITTER: {
 108                                 blitter->PaletteAnimate(this->local_palette);
 109                                 break;
 110                         }
 111
 112                         case Blitter::PALETTE_ANIMATION_NONE:
 113                                 break;
 114
 115                         default:
 116                                 NOT_REACHED();
 117                 }
 118                 this->local_palette.count_dirty = 0;
 119         }
 120
 121         SDL_Rect r = { this->dirty_rect.left, this->dirty_rect.top, this->dirty_rect.right - this->dirty_rect.left, this->dirty_rect.bottom - this->dirty_rect.top };
 122
 123         if (_sdl_surface != _sdl_real_surface) {
 124                 SDL_BlitSurface(_sdl_surface, &r, _sdl_real_surface, &r);
 125         }
 126         SDL_UpdateWindowSurfaceRects(this->sdl_window, &r, 1);
 127
 128         this->dirty_rect = {};
 129 }
 130
 131 bool VideoDriver_SDL_Default::AllocateBackingStore(int w, int h, bool force)
 132 {
 133         int bpp = BlitterFactory::GetCurrentBlitter()->GetScreenDepth();
 134
 135         _sdl_real_surface = SDL_GetWindowSurface(this->sdl_window);
 136         if (_sdl_real_surface == nullptr) usererror("SDL2: Couldn't get window surface: %s", SDL_GetError());
 137
 138         if (!force && w == _sdl_real_surface->w && h == _sdl_real_surface->h) return false;
 139
 140         /* Free any previously allocated rgb surface. */
 141         if (_sdl_rgb_surface != nullptr) {
 142                 SDL_FreeSurface(_sdl_rgb_surface);
 143                 _sdl_rgb_surface = nullptr;
 144         }
 145
 146         if (bpp == 8) {
 147                 _sdl_rgb_surface = SDL_CreateRGBSurface(0, w, h, 8, 0, 0, 0, 0);
 148                 if (_sdl_rgb_surface == nullptr) usererror("SDL2: Couldn't allocate shadow surface: %s", SDL_GetError());
 149
 150                 _sdl_surface = _sdl_rgb_surface;
 151         } else {
 152                 _sdl_surface = _sdl_real_surface;
 153         }
 154
 155         /* X11 doesn't appreciate it if we invalidate areas outside the window
 156          * if shared memory is enabled (read: it crashes). So, as we might have
 157          * gotten smaller, reset our dirty rects. GameSizeChanged() a bit lower
 158          * will mark the whole screen dirty again anyway, but this time with the
 159          * new dimensions. */
 160         this->dirty_rect = {};
 161
 162         _screen.width = _sdl_surface->w;
 163         _screen.height = _sdl_surface->h;
 164         _screen.pitch = _sdl_surface->pitch / (bpp / 8);
 165         _screen.dst_ptr = this->GetVideoPointer();
 166
 167         this->MakePalette();
 168
 169         return true;
 170 }
 171
 172 void *VideoDriver_SDL_Default::GetVideoPointer()
 173 {
 174         return _sdl_surface->pixels;
 175 }