scummvm/backends/sdl/sdl_gl.cpp

/* ScummVM - Scumm Interpreter
 * Copyright (C) 2001  Ludvig Strigeus
 * Copyright (C) 2001-2003 The ScummVM project
 *
 * This program 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; either version 2
 * of the License, or (at your option) any later version.

 * This program 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.  See the
 * GNU General Public License for more details.

 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 * $Header$
 *
 */

#include "sdl-common.h"
#include "common/scaler.h"
#include "common/util.h"
#include "common/engine.h"	// Only #included for error() and warning()

#ifdef WIN32
int glColorTable(int, int, int, int, int, void *) { return 0; }
int glGetColorTable(int, int, int, void *) { return 0; }
#endif

#include "fb2opengl.h"

class OSystem_SDL_OpenGL : public OSystem_SDL_Common {
public:
	OSystem_SDL_OpenGL() { 
	  _glScreenStart = 0; 
	  _glBilinearFilter = true;
	  _glBottomOfTexture = 256; // height is always 256
	}

	// Set colors of the palette
	void set_palette(const byte *colors, uint start, uint num);

	// Update the dirty areas of the screen
	void update_screen();

	// Set a parameter
	uint32 property(int param, Property *value);

protected:
	FB2GL fb2gl;
	int _glFlags;
	int _glScreenStart;
	bool _glBilinearFilter;
	SDL_Surface *tmpSurface; // Used for black rectangles blitting 
	SDL_Rect tmpBlackRect; // Black rectangle at end of the GL screen
	int _glBottomOfTexture;
	
	virtual void load_gfx_mode();
	virtual void unload_gfx_mode();
	void hotswap_gfx_mode();
};

OSystem_SDL_Common *OSystem_SDL_Common::create() {
	return new OSystem_SDL_OpenGL();
}

void OSystem_SDL_OpenGL::set_palette(const byte *colors, uint start, uint num) {
	const byte *b = colors;
	uint i;
	SDL_Color *base = _currentPalette + start;
	for(i = 0; i < num; i++) {
		base[i].r = b[0];
		base[i].g = b[1];
		base[i].b = b[2];
		b += 4;
	}

	if (start < _paletteDirtyStart)
		_paletteDirtyStart = start;

	if (start + num > _paletteDirtyEnd)
		_paletteDirtyEnd = start + num;
}

void OSystem_SDL_OpenGL::load_gfx_mode() {
	uint32 Rmask, Gmask, Bmask, Amask;
	// I have to force 16 bit color depth with 565 ordering
	// SDL_SetVideoMode sometimes doesn't accept your color depth definition
	Rmask = 0xF800; // 5
	Gmask = 0x07E0; // 6
	Bmask = 0x001F; // 5
	Amask = 0;
	
	_forceFull = true;
	_mode_flags = DF_UPDATE_EXPAND_1_PIXEL;
	_scaleFactor = 2;

	_tmpscreen = NULL;
	_tmpScreenWidth = (_screenWidth + 3);
	
	//
	// Create the surface that contains the 8 bit game data
	//
	_screen = SDL_CreateRGBSurface(SDL_SWSURFACE, _screenWidth, _screenHeight, 8, 0, 0, 0, 0);
	if (_screen == NULL)
		error("_screen failed");


	//
	// Create the surface that contains the scaled graphics in 16 bit mode
	//

	_glFlags =  FB2GL_320 | FB2GL_RGBA | FB2GL_16BIT;
	if (_full_screen) {
		_glFlags |= (FB2GL_FS);
		_glScreenStart = 0;
	}
	// 640x480 screen resolution
	fb2gl.init(640, 480, 0,_glScreenStart? 15: 70,_glFlags);

	SDL_SetGamma(1.25, 1.25, 1.25);

	
	//
	// Create the surface used for the graphics in 16 bit before scaling, and also the overlay
	//

	// Need some extra bytes around when using 2xSaI
	uint16 *tmp_screen = (uint16 *)calloc(_tmpScreenWidth * (_screenHeight + 3),sizeof(uint16));
	_tmpscreen = SDL_CreateRGBSurfaceFrom(tmp_screen,
						_tmpScreenWidth, _screenHeight + 3, 16, _tmpScreenWidth * 2,
						Rmask,
						Gmask,
						Bmask,
						Amask);

	tmpSurface = SDL_CreateRGBSurface(SDL_SWSURFACE, _screenWidth, 
						// 320x256 texture (black end)
						256-_screenHeight-_glScreenStart,
						16,
						Rmask,
						Gmask,
						Bmask,
						Amask);

	tmpBlackRect.x = 0;
	tmpBlackRect.y = 0;
	tmpBlackRect.w = _screenWidth;
	tmpBlackRect.h = 256-_screenHeight-_glScreenStart;

	if (_tmpscreen == NULL)
		error("_tmpscreen failed");

	// keyboard cursor control, some other better place for it?
	km.x_max = _screenWidth * _scaleFactor - 1;
	km.y_max = _screenHeight * _scaleFactor - 1;
	km.delay_time = 25;
	km.last_time = 0;
}

void OSystem_SDL_OpenGL::unload_gfx_mode() {
	SDL_SetGamma(1.0, 1.0, 1.0);
	if (_screen) {
		SDL_FreeSurface(_screen);
		_screen = NULL; 
	}

	if (_tmpscreen) {
		free((uint16 *)_tmpscreen->pixels);
		SDL_FreeSurface(_tmpscreen);
		_tmpscreen = NULL;
	}
}

void OSystem_SDL_OpenGL::hotswap_gfx_mode() {
	if (!_screen)
		return;

	// Keep around the old _screen & _tmpscreen so we can restore the screen data
	// after the mode switch.
	SDL_Surface *old_screen = _screen;
	SDL_Surface *old_tmpscreen = _tmpscreen;

	// Release the HW screen surface
	SDL_FreeSurface(fb2gl.getScreen());
	fb2gl.setScreen(NULL);

	// Setup the new GFX mode
	load_gfx_mode();

	// reset palette
	SDL_SetColors(_screen, _currentPalette, 0, 256);

	// Restore old screen content
	SDL_BlitSurface(old_screen, NULL, _screen, NULL);
	SDL_BlitSurface(old_tmpscreen, NULL, _tmpscreen, NULL);
	
	// Free the old surfaces
	SDL_FreeSurface(old_screen);
	free(old_tmpscreen->pixels);
	SDL_FreeSurface(old_tmpscreen);

	// Finally, blit everything to the screen
	update_screen();
}

void OSystem_SDL_OpenGL::update_screen() {
	// If the shake position changed, fill the dirty area with blackness
	if (_currentShakePos != _newShakePos) {
		SDL_Rect blackrect = {0, _glScreenStart, _screenWidth, _newShakePos+_glScreenStart};
		
		SDL_FillRect(tmpSurface, &blackrect, 0);
		fb2gl.blit16(tmpSurface, 1, &blackrect, 0, 0);

		_currentShakePos = _newShakePos;

		_forceFull = true;
	}

	// Make sure the mouse is drawn, if it should be drawn.
	draw_mouse();
	
	// Check whether the palette was changed in the meantime and update the
	// screen surface accordingly. 
	if (_paletteDirtyEnd != 0) {
		SDL_SetColors(_screen, _currentPalette + _paletteDirtyStart, 
			_paletteDirtyStart,
			_paletteDirtyEnd - _paletteDirtyStart);
		
		_paletteDirtyEnd = 0;

		_forceFull = true;
	}

	// Force a full redraw if requested
	if (_forceFull) {
		_num_dirty_rects = 1;

		_dirty_rect_list[0].x = 0;
		_dirty_rect_list[0].y = 0;
		_dirty_rect_list[0].w = _screenWidth;
		_dirty_rect_list[0].h = _screenHeight;
	}

	// Only draw anything if necessary
	if (_num_dirty_rects > 0) {
	
		SDL_Rect *r; 
		SDL_Rect *last_rect = _dirty_rect_list + _num_dirty_rects;
	
		// Convert appropriate parts of the 8bpp image into 16bpp
		if (!_overlayVisible) {
			SDL_Rect dst;
			for(r = _dirty_rect_list; r != last_rect; ++r) {
				dst = *r;
//				dst.x++;	// Shift rect by one since 2xSai needs to acces the data around
//				dst.y++;	// any pixel to scale it, and we want to avoid mem access crashes.
				if (SDL_BlitSurface(_screen, r, _tmpscreen, &dst) != 0)
					error("SDL_BlitSurface failed: %s", SDL_GetError());
			}
		}

		// Almost the same thing as SDL_UpdateRects
		fb2gl.blit16(_tmpscreen, _num_dirty_rects, _dirty_rect_list, 0,
									_currentShakePos+_glScreenStart);

		int _glBottomOfGameScreen = _screenHeight + _glScreenStart + _currentShakePos; 
		// Bottom black border height
		tmpBlackRect.h = _glBottomOfTexture - _glBottomOfGameScreen;
		
		if (!(_full_screen) && (tmpBlackRect.h > 0)) {
		  SDL_FillRect(tmpSurface, &tmpBlackRect, 0);
		  fb2gl.blit16(tmpSurface, 1, &tmpBlackRect, 0,
		      _glBottomOfGameScreen);
		}

		fb2gl.display();
	}

	_num_dirty_rects = 0;
	_forceFull = false;
}

uint32 OSystem_SDL_OpenGL::property(int param, Property *value) {
	int i;

	if (param == PROP_TOGGLE_FULLSCREEN) {
		_full_screen ^= true;
#ifdef MACOSX
		// On OS X, SDL_WM_ToggleFullScreen is currently not implemented. Worse,
		// it still always returns -1. So we simply don't call it at all and
		// use hotswap_gfx_mode() directly to switch to fullscreen mode.
		hotswap_gfx_mode();
#else
		if (!SDL_WM_ToggleFullScreen(fb2gl.getScreen())) {
			// if ToggleFullScreen fails, achieve the same effect with hotswap gfx mode
			hotswap_gfx_mode();
		}
#endif

		return 1;
	}
	else if (param == PROP_SET_GFX_MODE) {
		SDL_Rect full = {0, 0, _screenWidth, _screenHeight};
		glPopMatrix();

		switch(value->gfx_mode) {
			case 0: // Bilinear Filtering (on/off)
				_glBilinearFilter ^= true;
				for (i = 0; i < 2; i++) {
					glBindTexture(GL_TEXTURE_2D, i);
					if (_glBilinearFilter) {
						glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
						glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
					} else {
						glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
						glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
					}
				}
				break;
			case 1: // Don't use the whole screen
				fb2gl.init(0, 0, 0, 15, _glFlags);
				_glScreenStart = 20;
				SDL_FillRect(tmpSurface, &tmpBlackRect, 0);
				fb2gl.blit16(tmpSurface, 1, &tmpBlackRect, 0, 0);
				break;
			case 2: // Use the whole screen
				fb2gl.init(0, 0, 0, 70, _glFlags);
				_glScreenStart = 0;
				break;
			default: // Zooming
				glPushMatrix();
/*				SDL_FillRect(tmpSurface, &full, 0);
				fb2gl.blit16(tmpSurface, 1, &full,0, _glScreenStart);
				fb2gl.display();
				double x = (double)((_mouseCurState.x) 
						- (_screenWidth / 2)) / (_screenWidth / 2);
				double y = (double)((_mouseCurState.y) 
						- (_screenHeight / 2)) / (_screenHeight / 2);
				glTranslatef(-x, y, 0);
*/
				glScalef(1.0 + (double)(value->gfx_mode - 1) / 10,
						1.0 + (double)(value->gfx_mode - 1) / 10, 0);
		};
		fb2gl.blit16(_tmpscreen, 1, &full, 0, _glScreenStart);
		fb2gl.display();

		return 1;
	}

	return OSystem_SDL_Common::property(param, value);
}