ref: 52cee8eac843c5488cfe03fc1717dea5d2eb307c
dir: /textscreen/txt_sdl.c/
//
// Copyright(C) 2005-2014 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.
//
//
// Text mode emulation in SDL
//
#include "SDL.h"
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "doomkeys.h"
#include "txt_main.h"
#include "txt_sdl.h"
#if defined(_MSC_VER) && !defined(__cplusplus)
#define inline __inline
#endif
typedef struct
{
unsigned char *data;
unsigned int w;
unsigned int h;
} txt_font_t;
// Fonts:
#include "txt_font.h"
#include "txt_largefont.h"
#include "txt_smallfont.h"
// Time between character blinks in ms
#define BLINK_PERIOD 250
static SDL_Surface *screen;
static SDL_Surface *screenbuffer;
static unsigned char *screendata;
static int key_mapping = 1;
static TxtSDLEventCallbackFunc event_callback;
static void *event_callback_data;
static int modifier_state[TXT_NUM_MODIFIERS];
// Font we are using:
static txt_font_t *font;
//#define TANGO
#ifndef TANGO
static SDL_Color ega_colors[] =
{
{0x00, 0x00, 0x00, 0x00}, // 0: Black
{0x00, 0x00, 0xa8, 0x00}, // 1: Blue
{0x00, 0xa8, 0x00, 0x00}, // 2: Green
{0x00, 0xa8, 0xa8, 0x00}, // 3: Cyan
{0xa8, 0x00, 0x00, 0x00}, // 4: Red
{0xa8, 0x00, 0xa8, 0x00}, // 5: Magenta
{0xa8, 0x54, 0x00, 0x00}, // 6: Brown
{0xa8, 0xa8, 0xa8, 0x00}, // 7: Grey
{0x54, 0x54, 0x54, 0x00}, // 8: Dark grey
{0x54, 0x54, 0xfe, 0x00}, // 9: Bright blue
{0x54, 0xfe, 0x54, 0x00}, // 10: Bright green
{0x54, 0xfe, 0xfe, 0x00}, // 11: Bright cyan
{0xfe, 0x54, 0x54, 0x00}, // 12: Bright red
{0xfe, 0x54, 0xfe, 0x00}, // 13: Bright magenta
{0xfe, 0xfe, 0x54, 0x00}, // 14: Yellow
{0xfe, 0xfe, 0xfe, 0x00}, // 15: Bright white
};
#else
// Colors that fit the Tango desktop guidelines: see
// http://tango.freedesktop.org/ also
// http://uwstopia.nl/blog/2006/07/tango-terminal
static SDL_Color ega_colors[] =
{
{0x2e, 0x34, 0x36, 0x00}, // 0: Black
{0x34, 0x65, 0xa4, 0x00}, // 1: Blue
{0x4e, 0x9a, 0x06, 0x00}, // 2: Green
{0x06, 0x98, 0x9a, 0x00}, // 3: Cyan
{0xcc, 0x00, 0x00, 0x00}, // 4: Red
{0x75, 0x50, 0x7b, 0x00}, // 5: Magenta
{0xc4, 0xa0, 0x00, 0x00}, // 6: Brown
{0xd3, 0xd7, 0xcf, 0x00}, // 7: Grey
{0x55, 0x57, 0x53, 0x00}, // 8: Dark grey
{0x72, 0x9f, 0xcf, 0x00}, // 9: Bright blue
{0x8a, 0xe2, 0x34, 0x00}, // 10: Bright green
{0x34, 0xe2, 0xe2, 0x00}, // 11: Bright cyan
{0xef, 0x29, 0x29, 0x00}, // 12: Bright red
{0x34, 0xe2, 0xe2, 0x00}, // 13: Bright magenta
{0xfc, 0xe9, 0x4f, 0x00}, // 14: Yellow
{0xee, 0xee, 0xec, 0x00}, // 15: Bright white
};
#endif
#ifdef _WIN32
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
// Examine system DPI settings to determine whether to use the large font.
static int Win32_UseLargeFont(void)
{
HDC hdc = GetDC(NULL);
int dpix;
if (!hdc)
{
return 0;
}
dpix = GetDeviceCaps(hdc, LOGPIXELSX);
ReleaseDC(NULL, hdc);
// 144 is the DPI when using "150%" scaling. If the user has this set
// then consider this an appropriate threshold for using the large font.
return dpix >= 144;
}
#endif
static txt_font_t *FontForName(char *name)
{
if (!strcmp(name, "small"))
{
return &small_font;
}
else if (!strcmp(name, "normal"))
{
return &main_font;
}
else if (!strcmp(name, "large"))
{
return &large_font;
}
else
{
return NULL;
}
}
//
// Select the font to use, based on screen resolution
//
// If the highest screen resolution available is less than
// 640x480, use the small font.
//
static void ChooseFont(void)
{
const SDL_VideoInfo *info;
char *env;
// Allow normal selection to be overridden from an environment variable:
env = getenv("TEXTSCREEN_FONT");
if (env != NULL)
{
font = FontForName(env);
if (font != NULL)
{
return;
}
}
// Get desktop resolution:
info = SDL_GetVideoInfo();
// If in doubt and we can't get a list, always prefer to
// fall back to the normal font:
if (info == NULL)
{
font = &main_font;
return;
}
// On tiny low-res screens (eg. palmtops) use the small font.
// If the screen resolution is at least 1920x1080, this is
// a modern high-resolution display, and we can use the
// large font.
if (info->current_w < 640 || info->current_h < 480)
{
font = &small_font;
}
#ifdef _WIN32
// On Windows we can use the system DPI settings to make a
// more educated guess about whether to use the large font.
else if (Win32_UseLargeFont())
{
font = &large_font;
}
#endif
// TODO: Detect high DPI on Linux by inquiring about Gtk+ scale
// settings. This looks like it should just be a case of shelling
// out to invoke the 'gsettings' command, eg.
// gsettings get org.gnome.desktop.interface text-scaling-factor
// and using large_font if the result is >= 2.
else
{
font = &main_font;
}
}
//
// Initialize text mode screen
//
// Returns 1 if successful, 0 if an error occurred
//
int TXT_Init(void)
{
if (SDL_InitSubSystem(SDL_INIT_VIDEO) < 0)
{
return 0;
}
ChooseFont();
// Always create the screen at the native screen depth (bpp=0);
// some systems nowadays don't seem to support true 8-bit palettized
// screen modes very well and we end up with screwed up colors.
screen = SDL_SetVideoMode(TXT_SCREEN_W * font->w,
TXT_SCREEN_H * font->h, 0, 0);
if (screen == NULL)
return 0;
// Instead, we draw everything into an intermediate 8-bit surface
// the same dimensions as the screen. SDL then takes care of all the
// 8->32 bit (or whatever depth) color conversions for us.
screenbuffer = SDL_CreateRGBSurface(0, TXT_SCREEN_W * font->w,
TXT_SCREEN_H * font->h,
8, 0, 0, 0, 0);
SDL_SetColors(screenbuffer, ega_colors, 0, 16);
SDL_EnableUNICODE(1);
screendata = malloc(TXT_SCREEN_W * TXT_SCREEN_H * 2);
memset(screendata, 0, TXT_SCREEN_W * TXT_SCREEN_H * 2);
// Ignore all mouse motion events
// SDL_EventState(SDL_MOUSEMOTION, SDL_IGNORE);
// Repeat key presses so we can hold down arrows to scroll down the
// menu, for example. This is what setup.exe does.
SDL_EnableKeyRepeat(SDL_DEFAULT_REPEAT_DELAY, SDL_DEFAULT_REPEAT_INTERVAL);
return 1;
}
void TXT_Shutdown(void)
{
free(screendata);
screendata = NULL;
SDL_FreeSurface(screenbuffer);
screenbuffer = NULL;
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;
unsigned int bit, bytes;
int bg, fg;
unsigned int x1, y1;
p = &screendata[(y * TXT_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() / BLINK_PERIOD) % 2) == 0)
{
fg = bg;
}
}
// How many bytes per line?
bytes = (font->w + 7) / 8;
p = &font->data[character * font->h * bytes];
s = ((unsigned char *) screenbuffer->pixels)
+ (y * font->h * screenbuffer->pitch)
+ (x * font->w);
for (y1=0; y1<font->h; ++y1)
{
s1 = s;
bit = 0;
for (x1=0; x1<font->w; ++x1)
{
if (*p & (1 << (7-bit)))
{
*s1++ = fg;
}
else
{
*s1++ = bg;
}
++bit;
if (bit == 8)
{
++p;
bit = 0;
}
}
if (bit != 0)
{
++p;
}
s += screenbuffer->pitch;
}
}
static int LimitToRange(int val, int min, int max)
{
if (val < min)
{
return min;
}
else if (val > max)
{
return max;
}
else
{
return val;
}
}
void TXT_UpdateScreenArea(int x, int y, int w, int h)
{
SDL_Rect rect;
int x1, y1;
int x_end;
int y_end;
x_end = LimitToRange(x + w, 0, TXT_SCREEN_W);
y_end = LimitToRange(y + h, 0, TXT_SCREEN_H);
x = LimitToRange(x, 0, TXT_SCREEN_W);
y = LimitToRange(y, 0, TXT_SCREEN_H);
for (y1=y; y1<y_end; ++y1)
{
for (x1=x; x1<x_end; ++x1)
{
UpdateCharacter(x1, y1);
}
}
rect.x = x * font->w;
rect.y = y * font->h;
rect.w = (x_end - x) * font->w;
rect.h = (y_end - y) * font->h;
SDL_BlitSurface(screenbuffer, &rect, screen, &rect);
SDL_UpdateRects(screen, 1, &rect);
}
void TXT_UpdateScreen(void)
{
TXT_UpdateScreenArea(0, 0, TXT_SCREEN_W, TXT_SCREEN_H);
}
void TXT_GetMousePosition(int *x, int *y)
{
SDL_GetMouseState(x, y);
*x /= font->w;
*y /= font->h;
}
//
// Translates the SDL key
//
static int TranslateKey(SDL_keysym *sym)
{
switch(sym->sym)
{
case SDLK_LEFT: return KEY_LEFTARROW;
case SDLK_RIGHT: return KEY_RIGHTARROW;
case SDLK_DOWN: return KEY_DOWNARROW;
case SDLK_UP: return KEY_UPARROW;
case SDLK_ESCAPE: return KEY_ESCAPE;
case SDLK_RETURN: return KEY_ENTER;
case SDLK_TAB: return KEY_TAB;
case SDLK_F1: return KEY_F1;
case SDLK_F2: return KEY_F2;
case SDLK_F3: return KEY_F3;
case SDLK_F4: return KEY_F4;
case SDLK_F5: return KEY_F5;
case SDLK_F6: return KEY_F6;
case SDLK_F7: return KEY_F7;
case SDLK_F8: return KEY_F8;
case SDLK_F9: return KEY_F9;
case SDLK_F10: return KEY_F10;
case SDLK_F11: return KEY_F11;
case SDLK_F12: return KEY_F12;
case SDLK_PRINT: return KEY_PRTSCR;
case SDLK_BACKSPACE: return KEY_BACKSPACE;
case SDLK_DELETE: return KEY_DEL;
case SDLK_PAUSE: return KEY_PAUSE;
case SDLK_LSHIFT:
case SDLK_RSHIFT:
return KEY_RSHIFT;
case SDLK_LCTRL:
case SDLK_RCTRL:
return KEY_RCTRL;
case SDLK_LALT:
case SDLK_RALT:
case SDLK_LMETA:
case SDLK_RMETA:
return KEY_RALT;
case SDLK_CAPSLOCK: return KEY_CAPSLOCK;
case SDLK_SCROLLOCK: return KEY_SCRLCK;
case SDLK_HOME: return KEY_HOME;
case SDLK_INSERT: return KEY_INS;
case SDLK_END: return KEY_END;
case SDLK_PAGEUP: return KEY_PGUP;
case SDLK_PAGEDOWN: return KEY_PGDN;
#ifdef SDL_HAVE_APP_KEYS
case SDLK_APP1: return KEY_F1;
case SDLK_APP2: return KEY_F2;
case SDLK_APP3: return KEY_F3;
case SDLK_APP4: return KEY_F4;
case SDLK_APP5: return KEY_F5;
case SDLK_APP6: return KEY_F6;
#endif
default: break;
}
// Returned value is different, depending on whether key mapping is
// enabled. Key mapping is preferable most of the time, for typing
// in text, etc. However, when we want to read raw keyboard codes
// for the setup keyboard configuration dialog, we want the raw
// key code.
if (key_mapping)
{
// Unicode characters beyond the ASCII range need to be
// mapped up into textscreen's Unicode range.
if (sym->unicode < 128)
{
return sym->unicode;
}
else
{
return sym->unicode - 128 + TXT_UNICODE_BASE;
}
}
else
{
// Keypad mapping is only done when we want a raw value:
// most of the time, the keypad should behave as it normally
// does.
switch (sym->sym)
{
case SDLK_KP0: return KEYP_0;
case SDLK_KP1: return KEYP_1;
case SDLK_KP2: return KEYP_2;
case SDLK_KP3: return KEYP_3;
case SDLK_KP4: return KEYP_4;
case SDLK_KP5: return KEYP_5;
case SDLK_KP6: return KEYP_6;
case SDLK_KP7: return KEYP_7;
case SDLK_KP8: return KEYP_8;
case SDLK_KP9: return KEYP_9;
case SDLK_KP_PERIOD: return KEYP_PERIOD;
case SDLK_KP_MULTIPLY: return KEYP_MULTIPLY;
case SDLK_KP_PLUS: return KEYP_PLUS;
case SDLK_KP_MINUS: return KEYP_MINUS;
case SDLK_KP_DIVIDE: return KEYP_DIVIDE;
case SDLK_KP_EQUALS: return KEYP_EQUALS;
case SDLK_KP_ENTER: return KEYP_ENTER;
default:
return tolower(sym->sym);
}
}
}
// Convert an SDL button index to textscreen button index.
//
// Note special cases because 2 == mid in SDL, 3 == mid in textscreen/setup
static int SDLButtonToTXTButton(int button)
{
switch (button)
{
case SDL_BUTTON_LEFT:
return TXT_MOUSE_LEFT;
case SDL_BUTTON_RIGHT:
return TXT_MOUSE_RIGHT;
case SDL_BUTTON_MIDDLE:
return TXT_MOUSE_MIDDLE;
default:
return TXT_MOUSE_BASE + button - 1;
}
}
static int MouseHasMoved(void)
{
static int last_x = 0, last_y = 0;
int x, y;
TXT_GetMousePosition(&x, &y);
if (x != last_x || y != last_y)
{
last_x = x; last_y = y;
return 1;
}
else
{
return 0;
}
}
// Examine a key press/release and update the modifier key state
// if necessary.
static void UpdateModifierState(SDL_keysym *sym, int pressed)
{
txt_modifier_t mod;
switch (sym->sym)
{
case SDLK_LSHIFT:
case SDLK_RSHIFT:
mod = TXT_MOD_SHIFT;
break;
case SDLK_LCTRL:
case SDLK_RCTRL:
mod = TXT_MOD_CTRL;
break;
case SDLK_LALT:
case SDLK_RALT:
case SDLK_LMETA:
case SDLK_RMETA:
mod = TXT_MOD_ALT;
break;
default:
return;
}
if (pressed)
{
++modifier_state[mod];
}
else
{
--modifier_state[mod];
}
}
signed int TXT_GetChar(void)
{
SDL_Event ev;
while (SDL_PollEvent(&ev))
{
// If there is an event callback, allow it to intercept this
// event.
if (event_callback != NULL)
{
if (event_callback(&ev, event_callback_data))
{
continue;
}
}
// Process the event.
switch (ev.type)
{
case SDL_MOUSEBUTTONDOWN:
if (ev.button.button < TXT_MAX_MOUSE_BUTTONS)
{
return SDLButtonToTXTButton(ev.button.button);
}
break;
case SDL_KEYDOWN:
UpdateModifierState(&ev.key.keysym, 1);
return TranslateKey(&ev.key.keysym);
case SDL_KEYUP:
UpdateModifierState(&ev.key.keysym, 0);
break;
case SDL_QUIT:
// Quit = escape
return 27;
case SDL_MOUSEMOTION:
if (MouseHasMoved())
{
return 0;
}
default:
break;
}
}
return -1;
}
int TXT_GetModifierState(txt_modifier_t mod)
{
if (mod < TXT_NUM_MODIFIERS)
{
return modifier_state[mod] > 0;
}
return 0;
}
static const char *SpecialKeyName(int key)
{
switch (key)
{
case ' ': return "SPACE";
case KEY_RIGHTARROW: return "RIGHT";
case KEY_LEFTARROW: return "LEFT";
case KEY_UPARROW: return "UP";
case KEY_DOWNARROW: return "DOWN";
case KEY_ESCAPE: return "ESC";
case KEY_ENTER: return "ENTER";
case KEY_TAB: return "TAB";
case KEY_F1: return "F1";
case KEY_F2: return "F2";
case KEY_F3: return "F3";
case KEY_F4: return "F4";
case KEY_F5: return "F5";
case KEY_F6: return "F6";
case KEY_F7: return "F7";
case KEY_F8: return "F8";
case KEY_F9: return "F9";
case KEY_F10: return "F10";
case KEY_F11: return "F11";
case KEY_F12: return "F12";
case KEY_BACKSPACE: return "BKSP";
case KEY_PAUSE: return "PAUSE";
case KEY_EQUALS: return "EQUALS";
case KEY_MINUS: return "MINUS";
case KEY_RSHIFT: return "SHIFT";
case KEY_RCTRL: return "CTRL";
case KEY_RALT: return "ALT";
case KEY_CAPSLOCK: return "CAPS";
case KEY_SCRLCK: return "SCRLCK";
case KEY_HOME: return "HOME";
case KEY_END: return "END";
case KEY_PGUP: return "PGUP";
case KEY_PGDN: return "PGDN";
case KEY_INS: return "INS";
case KEY_DEL: return "DEL";
case KEY_PRTSCR: return "PRTSC";
/*
case KEYP_0: return "PAD0";
case KEYP_1: return "PAD1";
case KEYP_2: return "PAD2";
case KEYP_3: return "PAD3";
case KEYP_4: return "PAD4";
case KEYP_5: return "PAD5";
case KEYP_6: return "PAD6";
case KEYP_7: return "PAD7";
case KEYP_8: return "PAD8";
case KEYP_9: return "PAD9";
case KEYP_UPARROW: return "PAD_U";
case KEYP_DOWNARROW: return "PAD_D";
case KEYP_LEFTARROW: return "PAD_L";
case KEYP_RIGHTARROW: return "PAD_R";
case KEYP_MULTIPLY: return "PAD*";
case KEYP_PLUS: return "PAD+";
case KEYP_MINUS: return "PAD-";
case KEYP_DIVIDE: return "PAD/";
*/
default: return NULL;
}
}
void TXT_GetKeyDescription(int key, char *buf, size_t buf_len)
{
const char *keyname;
keyname = SpecialKeyName(key);
if (keyname != NULL)
{
TXT_StringCopy(buf, keyname, buf_len);
}
else if (isprint(key))
{
TXT_snprintf(buf, buf_len, "%c", toupper(key));
}
else
{
TXT_snprintf(buf, buf_len, "??%i", key);
}
}
// Searches the desktop screen buffer to determine whether there are any
// blinking characters.
int TXT_ScreenHasBlinkingChars(void)
{
int x, y;
unsigned char *p;
// Check all characters in screen buffer
for (y=0; y<TXT_SCREEN_H; ++y)
{
for (x=0; x<TXT_SCREEN_W; ++x)
{
p = &screendata[(y * TXT_SCREEN_W + x) * 2];
if (p[1] & 0x80)
{
// This character is blinking
return 1;
}
}
}
// None found
return 0;
}
// Sleeps until an event is received, the screen needs to be redrawn,
// or until timeout expires (if timeout != 0)
void TXT_Sleep(int timeout)
{
unsigned int start_time;
if (TXT_ScreenHasBlinkingChars())
{
int time_to_next_blink;
time_to_next_blink = BLINK_PERIOD - (SDL_GetTicks() % BLINK_PERIOD);
// There are blinking characters on the screen, so we
// must time out after a while
if (timeout == 0 || timeout > time_to_next_blink)
{
// Add one so it is always positive
timeout = time_to_next_blink + 1;
}
}
if (timeout == 0)
{
// We can just wait forever until an event occurs
SDL_WaitEvent(NULL);
}
else
{
// Sit in a busy loop until the timeout expires or we have to
// redraw the blinking screen
start_time = SDL_GetTicks();
while (SDL_GetTicks() < start_time + timeout)
{
if (SDL_PollEvent(NULL) != 0)
{
// Received an event, so stop waiting
break;
}
// Don't hog the CPU
SDL_Delay(1);
}
}
}
void TXT_EnableKeyMapping(int enable)
{
key_mapping = enable;
}
void TXT_SetWindowTitle(char *title)
{
SDL_WM_SetCaption(title, NULL);
}
void TXT_SDL_SetEventCallback(TxtSDLEventCallbackFunc callback, void *user_data)
{
event_callback = callback;
event_callback_data = user_data;
}
// Safe string functions.
void TXT_StringCopy(char *dest, const char *src, size_t dest_len)
{
if (dest_len < 1)
{
return;
}
dest[dest_len - 1] = '\0';
strncpy(dest, src, dest_len - 1);
}
void TXT_StringConcat(char *dest, const char *src, size_t dest_len)
{
size_t offset;
offset = strlen(dest);
if (offset > dest_len)
{
offset = dest_len;
}
TXT_StringCopy(dest + offset, src, dest_len - offset);
}
// On Windows, vsnprintf() is _vsnprintf().
#ifdef _WIN32
#if _MSC_VER < 1400 /* not needed for Visual Studio 2008 */
#define vsnprintf _vsnprintf
#endif
#endif
// Safe, portable vsnprintf().
int TXT_vsnprintf(char *buf, size_t buf_len, const char *s, va_list args)
{
int result;
if (buf_len < 1)
{
return 0;
}
// Windows (and other OSes?) has a vsnprintf() that doesn't always
// append a trailing \0. So we must do it, and write into a buffer
// that is one byte shorter; otherwise this function is unsafe.
result = vsnprintf(buf, buf_len, s, args);
// If truncated, change the final char in the buffer to a \0.
// A negative result indicates a truncated buffer on Windows.
if (result < 0 || result >= buf_len)
{
buf[buf_len - 1] = '\0';
result = buf_len - 1;
}
return result;
}
// Safe, portable snprintf().
int TXT_snprintf(char *buf, size_t buf_len, const char *s, ...)
{
va_list args;
int result;
va_start(args, s);
result = TXT_vsnprintf(buf, buf_len, s, args);
va_end(args);
return result;
}