gui_getbitmappixelindex.c

来自「LPC2368驱动淘宝上27元钱的TFT的代码」· C语言 代码 · 共 67 行

/*
*********************************************************************************************************
*   											 uC/GUI
*   					 Universal graphic software for embedded applications
*
*   					(c) Copyright 2002, Micrium Inc., Weston, FL
*   					(c) Copyright 2002, SEGGER Microcontroller Systeme GmbH
*
*   		   礐/GUI is protected by international copyright laws. Knowledge of the
*   		   source code may not be used to write a similar product. This file may
*   		   only be used in accordance with a license and should not be redistributed
*   		   in any way. We appreciate your understanding and fairness.
*
----------------------------------------------------------------------
File		: GUI_GetBitmapPixelIndex.c
Purpose 	: Implementation of GUI_GetBitmapPixelIndex
---------------------------END-OF-HEADER------------------------------
*/

#include "GUI_Private.h"

/*********************************************************************
*
*   	Public code
*
**********************************************************************
*/
/*********************************************************************
*
*   	GUI_GetBitmapPixelIndex
*/
int GUI_GetBitmapPixelIndex(const GUI_BITMAP GUI_UNI_PTR *pBMP, unsigned x, unsigned y)
{
	unsigned Off, Value;
	switch (pBMP->BitsPerPixel)
	{
		case 1:
			Off = (x >> 3) + (y * pBMP->BytesPerLine);
			Value = *(pBMP->pData + Off);
			Value = Value >> (7 - (x & 0x7)) & 0x1;
			break;
		case 2:
			Off = (x >> 2) + (y * pBMP->BytesPerLine);
			Value = *(pBMP->pData + Off);
			Value = Value >> (6 - ((x << 1) & 0x6)) & 0x3;
			break;
		case 4:
			Off = (x >> 1) + (y * pBMP->BytesPerLine);
			Value = *(pBMP->pData + Off);
			Value = (x & 1) ? (Value & 0xF) : (Value >> 4);
			break;
		case 8:
			Off = x + y * pBMP->BytesPerLine;
			Value = *(pBMP->pData + Off);
			break;
		case 16:
			Off = (x << 1) + y * pBMP->BytesPerLine;
			Value = *(pBMP->pData + Off) | (*(pBMP->pData + Off + 1) << 8);
			break;
		default:
			Value = 0;
	}
	return Value;
}

/*************************** End of file ****************************/