Diff: u8g_page.c

Revision:

0:972874f31c98

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/u8g_page.c	Wed Mar 07 12:49:14 2018 +0000
@@ -0,0 +1,82 @@
+/*
+
+  u8g_page.c
+  
+  page helper functions, only called by the dev handler.
+
+  Universal 8bit Graphics Library
+  
+  Copyright (c) 2011, olikraus@gmail.com
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without modification, 
+  are permitted provided that the following conditions are met:
+
+  * Redistributions of source code must retain the above copyright notice, this list 
+    of conditions and the following disclaimer.
+    
+  * Redistributions in binary form must reproduce the above copyright notice, this 
+    list of conditions and the following disclaimer in the documentation and/or other 
+    materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 
+  CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, 
+  INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR 
+  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
+  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 
+  NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
+  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 
+  STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
+  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 
+  ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.  
+  
+  
+*/
+
+#include "u8g.h"
+
+/*
+  setup page count structure
+  conditions: page_height <= total_height
+*/
+void u8g_page_Init(u8g_page_t *p, u8g_uint_t page_height, u8g_uint_t total_height )
+{
+  p->page_height = page_height;
+  p->total_height = total_height;
+  p->page = 0;
+  u8g_page_First(p);
+}
+
+void u8g_page_First(u8g_page_t *p)
+{
+  p->page_y0 = 0;
+  p->page_y1 = p->page_height;
+  p->page_y1--;
+  p->page = 0;
+}
+
+uint8_t u8g_page_Next(u8g_page_t * p)
+{
+  register u8g_uint_t y1;
+  p->page_y0 += p->page_height;
+  if ( p->page_y0 >= p->total_height )
+    return 0;
+  p->page++;
+  y1 = p->page_y1;
+  y1 += p->page_height;
+  if ( y1 >= p->total_height )
+  {
+    y1 = p->total_height;
+    y1--;
+  }
+  p->page_y1 = y1;
+  
+  return 1;
+}
+
+
+
+