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alpha blt palmos

PostPosted: Oct 4, 2004 @ 5:41pm
by Structure
Hi,

I just downloaded gapidraw 10 mins ago so please forgive me if this is obvious,

Im trying to target pocketpc and palmos during the design phase of my game, does the palmos support alpha blt using a second alpha surface?

I ask this cos the documentation seems to support CGapiSurface::AlphaBlt for palmos, but I don’t know how you load in the apha surface from a png as CGapiSurface::CreateSurface is only win32 on GDSURFACE_ALPHA.


Actuly while im here are there any unobvious no no’s when targeting palmos (other than the features stated not supported in the docs)

thanks

PostPosted: Oct 4, 2004 @ 7:51pm
by Johan

PostPosted: Oct 4, 2004 @ 9:02pm
by Structure
ahh ok,

is this set to change ever, beacuse things like this are mapping out how im going to develop,

ie what formats to make graphics in etc,

also is an alpha blit alot (ie over 20%) slower than a color key?

Edit: thinking about it I don’t see how this would work as youd have to save the image bitmap with a blended background, this would show though the image if it was 50% opaque then get blended with the destination 50%?

PostPosted: Oct 4, 2004 @ 9:42pm
by Johan

PostPosted: Oct 4, 2004 @ 11:43pm
by StephC

PostPosted: Oct 5, 2004 @ 6:43am
by Johan
StephC: Yep. We already provide zip file management on the Palm OS through a virtual file system (to work around that there is no "real" file system available), so TGA is very much a good solution.

PostPosted: Oct 5, 2004 @ 1:37pm
by Structure

PostPosted: Oct 5, 2004 @ 3:05pm
by Pejo Software - Per
[quote="Structure"]
also is an alpha blit alot (ie over 20%) slower than a color key?
quote]
I think alpha blits are substantially slower than normal blits since I don't think you can operate on 2 pixels at the same time there. I am at least not doing it in in my framework, Johan Please correct me if GapiDraw does this.

PostPosted: Oct 5, 2004 @ 3:59pm
by Johan

PostPosted: Oct 5, 2004 @ 4:05pm
by StephC

PostPosted: Oct 5, 2004 @ 4:33pm
by Structure

PostPosted: Oct 5, 2004 @ 8:18pm
by Pejo Software - Per

PostPosted: Oct 5, 2004 @ 9:18pm
by Structure

PostPosted: Oct 5, 2004 @ 9:43pm
by Johan

PostPosted: Oct 5, 2004 @ 10:31pm
by Structure