ref: 693828adb286b6c1ec6d0b90f49c6947e6c6dd6e
dir: /textscreen/txt_main.c/
// Emacs style mode select -*- C++ -*-
//-----------------------------------------------------------------------------
//
// $Id: txt_main.c 183 2005-10-09 20:19:21Z fraggle $
//
// Copyright(C) 1993-1996 Id Software, Inc.
// Copyright(C) 2005 Simon Howard
//
// 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.
//
// $Log$
// Revision 1.3 2005/10/09 20:19:21 fraggle
// Handle blinking text in ENDOOM lumps properly.
//
// Revision 1.2 2005/10/09 16:42:46 fraggle
// Cannot do arithmetic on void pointers in standard C
//
// Revision 1.1 2005/10/02 03:16:03 fraggle
// Text mode emulation code
//
//
//-----------------------------------------------------------------------------
//
// Text mode emulation in SDL
//
//-----------------------------------------------------------------------------
#include <SDL.h>
#include <stdlib.h>
#include <string.h>
#include "txt_main.h"
#include "txt_font.h"
#define SCREEN_W 80
#define SCREEN_H 25
#define CHAR_W 8
#define CHAR_H 16
static SDL_Surface *screen;
static unsigned char *screendata;
static SDL_Color ega_colors[] =
{
{0x00, 0x00, 0x00}, // 0: Black
{0x00, 0x00, 0xa8}, // 1: Blue
{0x00, 0xa8, 0x00}, // 2: Green
{0x00, 0xa8, 0xa8}, // 3: Cyan
{0xa8, 0x00, 0x00}, // 4: Red
{0xa8, 0x00, 0xa8}, // 5: Magenta
{0xa8, 0x54, 0x00}, // 6: Brown
{0xa8, 0xa8, 0xa8}, // 7: Grey
{0x54, 0x54, 0x54}, // 8: Dark grey
{0x54, 0x54, 0xfe}, // 9: Bright blue
{0x54, 0xfe, 0x54}, // 10: Bright green
{0x54, 0xfe, 0xfe}, // 11: Bright cyan
{0xfe, 0x54, 0x54}, // 12: Bright red
{0xfe, 0x54, 0xfe}, // 13: Bright magenta
{0xfe, 0xfe, 0x54}, // 14: Yellow
{0xfe, 0xfe, 0xfe}, // 15: Bright white
};
//
// Initialise text mode screen
//
// Returns 1 if successful, 0 if an error occurred
//
int TXT_Init(void)
{
SDL_InitSubSystem(SDL_INIT_VIDEO);
screen = SDL_SetVideoMode(SCREEN_W * CHAR_W, SCREEN_H * CHAR_H, 8, 0);
if (screen == NULL)
return 0;
SDL_SetColors(screen, ega_colors, 0, 16);
screendata = malloc(SCREEN_W * SCREEN_H * 2);
memset(screendata, 0, SCREEN_W * SCREEN_H * 2);
return 1;
}
void TXT_Shutdown(void)
{
free(screendata);
SDL_QuitSubSystem(SDL_INIT_VIDEO);
}
unsigned char *TXT_GetScreenData(void)
{
return screendata;
}
static inline void UpdateCharacter(int x, int y)
{
unsigned char character;
unsigned char *p;
unsigned char *s, *s1;
int bg, fg;
int x1, y1;
p = &screendata[(y * SCREEN_W + x) * 2];
character = p[0];
fg = p[1] & 0xf;
bg = (p[1] >> 4) & 0xf;
if (bg & 0x8)
{
// blinking
bg &= ~0x8;
if (SDL_GetTicks() % 500 < 250)
fg = bg;
}
p = &int10_font_16[character * CHAR_H];
s = ((unsigned char *) screen->pixels)
+ (y * CHAR_H * screen->pitch) + (x * CHAR_W);
for (y1=0; y1<CHAR_H; ++y1)
{
s1 = s;
for (x1=0; x1<CHAR_W; ++x1)
{
if (*p & (1 << (7-x1)))
{
*s1++ = fg;
}
else
{
*s1++ = bg;
}
}
++p;
s += screen->pitch;
}
}
void TXT_UpdateScreenArea(int x, int y, int w, int h)
{
int x1, y1;
for (y1=y; y1<y+h; ++y1)
{
for (x1=x; x1<x+w; ++x1)
{
UpdateCharacter(x1, y1);
}
}
SDL_UpdateRect(screen, x * CHAR_W, y * CHAR_H, w * CHAR_W, h * CHAR_H);
}
void TXT_UpdateScreen(void)
{
TXT_UpdateScreenArea(0, 0, SCREEN_W, SCREEN_H);
}