Hi!

I'm trying to have an image to rotate over a dialog. In order to do so, I tried the following example (which is not an image I concede):

// ****************************************
// Function
//****************************************
void DrawRotatingIcon(void)
{
GUI_MEMDEV_Handle hMemSource = 0;
GUI_MEMDEV_Handle hMemDest = 0;
GUI_RECT RectSource = { 0, 0, 69, 39 };
GUI_RECT RectDest = { 0, 0, 79, 79 };


hMemSource = GUI_MEMDEV_CreateFixed(RectSource.x0,
RectSource.y0,
RectSource.x1 - RectSource.x0 + 1,
RectSource.y1 - RectSource.y0 + 1,
GUI_MEMDEV_NOTRANS,
GUI_MEMDEV_APILIST_32,
GUI_COLOR_CONV_888);

hMemDest = GUI_MEMDEV_CreateFixed(RectDest.x0,
RectDest.y0,
RectDest.x1 - RectDest.x0 + 1,
RectDest.y1 - RectDest.y0 + 1,
GUI_MEMDEV_NOTRANS,
GUI_MEMDEV_APILIST_32,
GUI_COLOR_CONV_888);

if (0 != hMemSource && 0 != hMemDest)
{
GUI_MEMDEV_Select(hMemSource);
GUI_DrawGradientV(RectSource.x0,
RectSource.y0,
RectSource.x1,
RectSource.y1,
GUI_WHITE,
GUI_DARKGREEN);
GUI_SetColor(GUI_BLUE);
GUI_SetFont(&GUI_Font20B_ASCII);
GUI_SetTextMode(GUI_TM_TRANS);
GUI_DispStringInRect("emWin", &RectSource, GUI_TA_HCENTER | GUI_TA_VCENTER);
GUI_DrawRect(0, 0, RectSource.x1, RectSource.y1);

static int rotation = 0;

GUI_MEMDEV_Select(hMemDest);
GUI_Clear();

GUI_MEMDEV_Select(0);

GUI_MEMDEV_RotateHQ(hMemSource,
hMemDest,
(RectDest.x1 - RectSource.x1) / 2,
(RectDest.y1 - RectSource.y1) / 2,
rotation * 1000,
1 * 1000);

//GUI_MEMDEV_CopyToLCDAt(hMemSource, 10, (RectDest.y1 - RectSource.y1) / 2 + 100);
GUI_MEMDEV_CopyToLCDAt(hMemDest, 100, 100);

if (rotation < 350)
{
rotation = rotation + 10;
}
else
{
rotation = 0;
}
}

if(0 != hMemSource)
{
GUI_MEMDEV_Delete(hMemSource);
}

if(0 != hMemDest)
{
GUI_MEMDEV_Delete(hMemDest);
}
}
// ****************************************
// End of Function
//****************************************


I call this function periodically while the dialog window is being displayed. Note that this rotating icon is displayed over the dialog. Since I am not using double buffering, the first problem I encountered was that at some point, when the dialog was being repainted, I lost my rotating icon until it was redrawn.

In order to eliminated that problem, I though about redrawing this icon both: periodically and whenever the dialog is repainted. In order to do so, I added a call to this same funtion on a WM_PAINT or WM_POSTPAINT callback. However, now the other widgets on the dialog do not get displayed corrected even though they do not physically overlap with the MEMDEV area. For example, if I press on a button, it will disappear.

What am I doing wrong? How would you recommand to implement a rotating image over a dialog? Can I rotate an Image widget and make it part of the dialog? I have not found how to do that.

Any thoughts?

Thanks!
Mathieu

The thing is, the rotating image is not part of the dialog. It's not a widget. I cannot invalidate it. Plus I already tried to draw the rotating image within a WM_PAINT. Actually, that is when the problem happens: button widget will disappear when pressed.

There seems to be a conflict with using MEMDEV within a WM_PAINT. I have no idea what to do to solve this.

Mathieu