From 937725f6749bced2526a13ebb8772233986917e3 Mon Sep 17 00:00:00 2001
From: Jens Arnold <amiconn@rockbox.org>
Date: Tue, 12 Jul 2005 23:50:37 +0000
Subject: [PATCH] Beginnings of a library complementing the core LCD functions.
 First function: filled triangle drawing.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@7128 a1c6a512-1295-4272-9138-f99709370657
---
 apps/plugins/lib/SOURCES |   3 ++
 apps/plugins/lib/xlcd.c  | 109 +++++++++++++++++++++++++++++++++++++++
 apps/plugins/lib/xlcd.h  |  34 ++++++++++++
 3 files changed, 146 insertions(+)
 create mode 100644 apps/plugins/lib/xlcd.c
 create mode 100644 apps/plugins/lib/xlcd.h

diff --git a/apps/plugins/lib/SOURCES b/apps/plugins/lib/SOURCES
index 49abf854da..00cc6d82c4 100644
--- a/apps/plugins/lib/SOURCES
+++ b/apps/plugins/lib/SOURCES
@@ -31,6 +31,9 @@ gray_set_foreground.c
 gray_setfont.c
 gray_verline.c
 #endif
+#ifdef HAVE_LCD_BITMAP
+xlcd.c
+#endif
 #ifdef HAVE_LCD_CHARCELLS
 playergfx.c
 #endif
diff --git a/apps/plugins/lib/xlcd.c b/apps/plugins/lib/xlcd.c
new file mode 100644
index 0000000000..a0dcc2ac3e
--- /dev/null
+++ b/apps/plugins/lib/xlcd.c
@@ -0,0 +1,109 @@
+/***************************************************************************
+*             __________               __   ___.
+*   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+*   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+*   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+*   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+*                     \/            \/     \/    \/            \/
+* $Id$
+*
+* Additional LCD routines not present in the core itself
+*
+* Copyright (C) 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.
+*
+****************************************************************************/
+
+#include "plugin.h"
+
+#ifdef HAVE_LCD_BITMAP
+
+/*** globals ***/
+
+static struct plugin_api *local_rb = NULL; /* global api struct pointer */
+
+/*** functions ***/
+
+/* library init */
+void xlcd_init(struct plugin_api* newrb)
+{
+    local_rb = newrb;
+}
+
+/* draw a filled triangle */
+void xlcd_filltriangle(int x1, int y1, int x2, int y2, int x3, int y3)
+{
+    int x, y;
+    long fp_y1, fp_y2, fp_dy1, fp_dy2;
+
+    /* sort vertices by increasing x value */
+    if (x1 > x3)
+    {
+        if (x2 < x3)       /* x2 < x3 < x1 */
+        {
+            x = x1; x1 = x2; x2 = x3; x3 = x;
+            y = y1; y1 = y2; y2 = y3; y3 = y;
+        }
+        else if (x2 > x1)  /* x3 < x1 < x2 */
+        {
+            x = x1; x1 = x3; x3 = x2; x2 = x;
+            y = y1; y1 = y3; y3 = y2; y2 = y;
+        }
+        else               /* x3 <= x2 <= x1 */
+        {
+            x = x1; x1 = x3; x3 = x;
+            y = y1; y1 = y3; y3 = y;
+        }
+    }
+    else
+    {
+        if (x2 < x1)       /* x2 < x1 <= x3 */
+        {
+            x = x1; x1 = x2; x2 = x;
+            y = y1; y1 = y2; y2 = y;
+        }
+        else if (x2 > x3)  /* x1 <= x3 < x2 */
+        {
+            x = x2; x2 = x3; x3 = x;
+            y = y2; y2 = y3; y3 = y;
+        }
+        /* else already sorted */
+    }
+
+    if (x1 < x3)  /* draw */
+    {
+        fp_dy1 = ((y3 - y1) << 16) / (x3 - x1);
+        fp_y1  = (y1 << 16) + (1<<15) + (fp_dy1 >> 1);
+
+        if (x1 < x2)  /* first part */
+        {   
+            fp_dy2 = ((y2 - y1) << 16) / (x2 - x1);
+            fp_y2  = (y1 << 16) + (1<<15) + (fp_dy2 >> 1);
+            for (x = x1; x < x2; x++)
+            {
+                local_rb->lcd_vline(x, fp_y1 >> 16, fp_y2 >> 16);
+                fp_y1 += fp_dy1;
+                fp_y2 += fp_dy2;
+            }
+        }
+        if (x2 < x3)  /* second part */
+        {
+            fp_dy2 = ((y3 - y2) << 16) / (x3 - x2);
+            fp_y2 = (y2 << 16) + (1<<15) + (fp_dy2 >> 1);
+            for (x = x2; x < x3; x++)
+            {
+                local_rb->lcd_vline(x, fp_y1 >> 16, fp_y2 >> 16);
+                fp_y1 += fp_dy1;
+                fp_y2 += fp_dy2;
+            }
+        }
+    }
+}
+
+#endif /* HAVE_LCD_BITMAP */
+
diff --git a/apps/plugins/lib/xlcd.h b/apps/plugins/lib/xlcd.h
new file mode 100644
index 0000000000..3f54643ec9
--- /dev/null
+++ b/apps/plugins/lib/xlcd.h
@@ -0,0 +1,34 @@
+/***************************************************************************
+*             __________               __   ___.
+*   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+*   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+*   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+*   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+*                     \/            \/     \/    \/            \/
+* $Id$
+*
+* Additional LCD routines not present in the core itself
+*
+* Copyright (C) 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 __XLCD_H__
+#define __XLCD_H__
+
+#include "plugin.h"
+
+#ifdef HAVE_LCD_BITMAP
+
+void xlcd_init(struct plugin_api* newrb);
+void xlcd_filltriangle(int x1, int y1, int x2, int y2, int x3, int y3);
+
+#endif /* HAVE_LCD_BITMAP */
+#endif /* __XLCD_H__ */
+