/*-----------------------------------------------------------------------------
* FUNCTION: SCRSVR_PicOnUsrMessage
* SCOPE: Screen saver screen related function - local
* DESCRIPTION: User message handler function for picture object, to redraw the last picture position by background color
*
* PARAMETERS: pMsg - pointer to D4D_MESSAGE structure
*
* RETURNS: return if this message discard or not
*-----------------------------------------------------------------------------*/
static Byte SCRSVR_PicOnUsrMessage(D4D_MESSAGE* pMsg)
{
if(pMsg->nMsgId == D4D_MSG_DRAWDONE)
{
D4D_SIZE pictSize = D4D_GetBmpSize(((D4D_PICTURE*)scrsvr_picLogo.pParam)->pBmp);
D4D_SIZE rectSize;
D4D_POINT rectPoint;
// Draw the horizontal box
rectSize.cy = D4D_Abs16(dy);
rectSize.cx = pictSize.cx;
rectPoint = oldPos;
if(oldPos.y > scrsvr_picLogo.position.y)
rectPoint.y += pictSize.cy;
D4D_FillRect(&rectPoint, &rectSize, D4D_COLOR_BLACK);
// Draw the vertical box
rectSize.cx = D4D_Abs16(dx);
rectSize.cy = pictSize.cy;
rectPoint = oldPos;
if(oldPos.x > scrsvr_picLogo.position.x)
rectPoint.x += pictSize.cx;
D4D_FillRect(&rectPoint, &rectSize, D4D_COLOR_BLACK);
}
return D4D_MSG_NOSKIP;
}
void D4D_LCD_Line (D4D_COOR x1, D4D_COOR y1, D4D_COOR x2, D4D_COOR y2, D4D_LINETYPE line_type, D4D_COLOR color) //draw line - bresenham algorithm
{
sWord delta_x, delta_y;
sByte ix, iy;
if((x1 == x2) || (y1 == y2)) // if the line is vertical or horizontal then draw box function is faster than general bresenham algorithm
{
if(line_type == D4D_LINE_THICK)
{
if(x1 > x2)
{
D4D_LCD_SwapCoor(&x1, &x2);
}
if(y1 > y2)
{
D4D_LCD_SwapCoor(&y1, &y2);
}
x2++;
y2++;
}
D4D_LCD_Box(x1 ,y1 ,x2 , y2, color);
return;
}
delta_x = (sWord)(D4D_Abs16((sWord)(x2 - x1)) << 1);
delta_y = (sWord)(D4D_Abs16((sWord)(y2 - y1)) << 1);
// if x1 == x2 or y1 == y2, then it does not matter what we set here
ix = (sByte)((x2 > x1)?1:-1);
iy = (sByte)((y2 > y1)?1:-1);
D4D_LCD_PutPixel((D4D_COOR) x1, (D4D_COOR) y1, line_type, color);
if (delta_x >= delta_y)
{
// error may go below zero
sLWord error = delta_y - (delta_x >> 1);
while (x1 != x2)
{
if (error >= 0)
{
if (error || (ix > 0))
{
y1 += iy;
error -= delta_x;
}
// else do nothing
}
// else do nothing
x1 += ix;
error += delta_y;
D4D_LCD_PutPixel((D4D_COOR) x1, (D4D_COOR) y1, line_type, color);
}
}
