ref: e5d6ce3318a59a18f25a632fa5ba0fd6801d7a3f
parent: 9c1d6d6f34af6699d272020757ca36a4daebe884
author: Simon Howard <fraggle@gmail.com>
date: Thu Aug 31 14:08:43 EDT 2006
More efficient TXT_Sleep function that puts the textscreen code to sleep until an event is received or the screen needs to blink. Subversion-branch: /trunk/chocolate-doom Subversion-revision: 570
--- a/textscreen/txt_main.c
+++ b/textscreen/txt_main.c
@@ -1,7 +1,7 @@
// Emacs style mode select -*- C++ -*-
//-----------------------------------------------------------------------------
//
-// $Id: txt_main.c 547 2006-06-02 19:29:24Z fraggle $
+// $Id: txt_main.c 570 2006-08-31 18:08:43Z fraggle $
//
// Copyright(C) 1993-1996 Id Software, Inc.
// Copyright(C) 2005 Simon Howard
@@ -57,6 +57,10 @@
#define CHAR_W 8
#define CHAR_H 16
+// Time between character blinks in ms
+
+#define BLINK_PERIOD 250
+
static SDL_Surface *screen;
static unsigned char *screendata;
@@ -101,6 +105,10 @@
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);
+
return 1;
}
@@ -135,8 +143,10 @@
bg &= ~0x8;
- if (SDL_GetTicks() % 500 < 250)
+ if (((SDL_GetTicks() / BLINK_PERIOD) % 2) == 0)
+ {fg = bg;
+ }
}
p = &int10_font_16[character * CHAR_H];
@@ -386,6 +396,89 @@
else
{sprintf(buf, "??%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)
+{+ 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);
+ }
}
}
--- a/textscreen/txt_main.h
+++ b/textscreen/txt_main.h
@@ -1,7 +1,7 @@
// Emacs style mode select -*- C++ -*-
//-----------------------------------------------------------------------------
//
-// $Id: txt_main.h 547 2006-06-02 19:29:24Z fraggle $
+// $Id: txt_main.h 570 2006-08-31 18:08:43Z fraggle $
//
// Copyright(C) 1993-1996 Id Software, Inc.
// Copyright(C) 2005 Simon Howard
@@ -104,6 +104,11 @@
// Retrieve the current position of the mouse
void TXT_GetMouseState(int *x, int *y);
+
+// Sleep until an event is received or the screen needs updating
+// Optional timeout in ms (timeout == 0 : sleep forever)
+
+void TXT_Sleep(int timeout);
#endif /* #ifndef TXT_MAIN_H */