what versions?  what gpu?

No, it will go to the GPU ... for a blit, try the shared memory flag ... failing this, create and offscreen context, and
 use it instead of a memory context .to see what happens.

-----Original Message-----
From: David McMinn [mailto:community-noreply@qnx.com] 
Sent: January 30, 2012 9:55 AM
To: photon-graphics
Subject: Re: RE: How to use PgBlit correctly?

Hi Derek,

Thanks for the reply.

PgBlit() never returns -1, always something >= 0 which according to the documentation is a success.

I added PgFlush() and PgWaitHWIdle() after drawing the line but it did not make a difference.

However, your reply got me thinking that I am maybe still doing something wrong or trying to use PgBlit() in an 
unsupported way. Just to re-iterate, this is through a memory context.

My code to create the image is below. Note that I don't use shared memory. I'm trying to draw to an in memory image so 
that I can display the image it in a widget, save it to a file and stream it to a printer (currently unsupported so I'm 
sending raw printer commands to an LPT port rather than use a printer context). I'm assuming that PhCreateImage() 
without the shared memory flag and the fact that I'm using a memory context means the image is all in CPU memory rather 
than video memory. Does PgBlit() work in that way (I assumed it would be done by the CPU rather than a GPU)?

    PhDim_t image_size = {100, 100};
    if (PhCreateImage(&g_MasterImage, image_size.w, image_size.h, Pg_IMAGE_DIRECT_888, NULL, 0, 0))



> Does the PgBlit() return -1?  I would put a PgFlush() and a 
> PgWaitHWIdle() right after the PgDrawLine() ... you have to make sure 
> everything is flushed out before blitting ... give it a try.
> 
> -----Original Message-----
> From: David McMinn [mailto:community-noreply@qnx.com]
> Sent: January 28, 2012 5:38 PM
> To: photon-graphics
> Subject: How to use PgBlit correctly?
> 
> Hello,
> 
> I am trying to use PgBlit() to copy an area of an image to another 
> location in  the same image. Can PgBlit() can be used for this purpose?
> 
> I can't seem to get it to work though. I have a PhImage_t and am 
> displaying it  in a PtImageArea. I am using a memory context to draw 
> to the image and I can see it updating (I draw lines to see that the 
> image updates) but I do not see the movement that I think should be caused by the PgBlit() call.
> 
> The code I am using is shown below. Is there something that I am doing 
> that is  wrong?
> 
> Thanks.
> 
> 
>     PmMemoryContext_t	*mc;		// Memory context to draw onto image
>     PhDim_t 			image_size = g_MasterImage.size;
>     PhPoint_t			origin = {0, 0};
> 
>     mc = PmMemCreateMC(&g_MasterImage, &image_size, &origin);
>     if (mc)
>     {
>     	// Set memory context as current draw context
>         PmMemStart(mc);
> 
>         PhRect_t	area;
>         PhPoint_t	offset;
> 
>         area.ul.x = 0;
>         area.ul.y = 40;
>         area.lr.x = g_MasterImage.size.w - 1;
>         area.lr.y = 85;
> 
>         offset.x = 0;
>         offset.y = 10;
> 
>         PgSetStrokeColor(Pg_WHITE);
>         PgDrawILine(rand() % g_MasterImage.size.w,
>                 rand() % g_MasterImage.size.h,
>                 rand() % g_MasterImage.size.w,
>                 rand() % g_MasterImage.size.h);
> 
>         if (PgBlit(&area, &offset) < 0)
>         {
>             printf("Blit failed");
>         }
> 
>         PgFlush();
>         PmMemStop(mc);
>         PmMemReleaseMC(mc);
>     }
> 
>     // Update image
>     PtSetResource(ABW_ImageView, Pt_ARG_IMAGEAREA_IMAGE, 
> &g_MasterImage, 0);
> 
> 
> 
> 
> _______________________________________________
> 
> Photon...