Complete rework of the grayscale library: (1) Implemented the new rockbox graphics api. (2) Added buffered mode, and implemented most drawing functions for buffered mode only. Buffered mode will ease implementation of animated graphics. Some functions are additionally provided as unbuffered versions (drawing grayscale bitmaps, scrolling) since unbuffered mode is better suited for non-animated graphics (JPEG viewer, mandelbrot) and saves some RAM, which is important on Archos. (3) Put all functions in a couple of source files, no more one-function-per-files. This became possible since sectioned compilation for the plugin library and appropriate linking for the pluginswas introduced, otherwise the binaries would be bloated by unused functions.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@7241 a1c6a512-1295-4272-9138-f99709370657

apps/plugins/lib/gray_parm.c

@@ -0,0 +1,107 @@
+/***************************************************************************
+*             __________               __   ___.
+*   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+*   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+*   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+*   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+*                     \/            \/     \/    \/            \/
+* $Id$
+*
+* Greyscale framework
+* Parameter handling
+*
+* This is a generic framework to use grayscale display within Rockbox
+* plugins. It obviously does not work for the player.
+*
+* Copyright (C) 2004-2005 Jens Arnold
+*
+* All files in this archive are subject to the GNU General Public License.
+* See the file COPYING in the source tree root for full license agreement.
+*
+* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+* KIND, either express or implied.
+*
+****************************************************************************/
+
+#ifndef SIMULATOR /* not for simulator by now */
+#include "plugin.h"
+
+#ifdef HAVE_LCD_BITMAP /* and also not for the Player */
+#include "gray.h"
+
+/* Set position of the top left corner of the greyscale overlay
+   Note that by is in pixel-block units (8 on Archos/SH1, 4 on H1x0) */
+void gray_set_position(int x, int by)
+{
+    _gray_info.x = x;
+    _gray_info.by = by;
+    
+    if (_gray_info.flags & _GRAY_RUNNING)
+        _gray_info.flags |= _GRAY_DEFERRED_UPDATE;
+}
+
+/* Set the draw mode for subsequent drawing operations */
+void gray_set_drawmode(int mode)
+{
+    _gray_info.drawmode = mode & (DRMODE_SOLID|DRMODE_INVERSEVID);
+}
+
+/* Return the current draw mode */
+int  gray_get_drawmode(void)
+{
+    return _gray_info.drawmode;
+}
+
+/* Set the foreground shade for subsequent drawing operations */
+void gray_set_foreground(int brightness)
+{
+    unsigned data = MULU16(_LEVEL_FAC * _gray_info.depth, brightness & 0xFF) + 127;
+
+    _gray_info.fg_brightness = (data + (data >> 8)) >> 8; /* approx. data / 255 */
+}
+
+/* Return the current foreground shade */
+int  gray_get_foreground(void)
+{
+    return (_gray_info.fg_brightness * 255 + ((_LEVEL_FAC * _gray_info.depth) >> 1))
+           / (_LEVEL_FAC * _gray_info.depth);
+}
+
+/* Set the background shade for subsequent drawing operations */
+void gray_set_background(int brightness)
+{
+    unsigned data = MULU16(_LEVEL_FAC * _gray_info.depth, brightness & 0xFF) + 127;
+
+    _gray_info.bg_brightness = (data + (data >> 8)) >> 8; /* approx. data / 255 */
+}
+
+/* Return the current background shade */
+int  gray_get_background(void)
+{
+    return (_gray_info.bg_brightness * 255 + ((_LEVEL_FAC * _gray_info.depth) >> 1))
+           / (_LEVEL_FAC * _gray_info.depth);
+}
+
+/* Set draw mode, foreground and background shades at once */
+void gray_set_drawinfo(int mode, int fg_brightness, int bg_brightness)
+{
+    gray_set_drawmode(mode);
+    gray_set_foreground(fg_brightness);
+    gray_set_background(bg_brightness);
+}
+
+/* Set font for the text output routines */
+void gray_setfont(int newfont)
+{
+    _gray_info.curfont = newfont;
+}
+
+/* Get width and height of a text when printed with the current font */
+int  gray_getstringsize(const unsigned char *str, int *w, int *h)
+{
+    return _gray_rb->font_getstringsize(str, w, h, _gray_info.curfont);
+}
+
+#endif /* HAVE_LCD_BITMAP */
+#endif /* !SIMULATOR */
+