Author Topic: Low range of blitting transparency  (Read 781 times)

Offline Irony

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Low range of blitting transparency
« on: December 25, 2012, 09:34:35 pm »
Hi,
first of all, thank you Egon for the great Engine. I am using it for a Wing-Commander-like space game (quite a niche on Android), which is making good progress.

My question: When I do a blit, and set the transparency value higher than ~ 10, the blit is fully opaque. Below that, it varies from fully transparent to opaque like it should. But it seems strange that the range of transparency is so low, like only 3 or 4 bits from transValue are actually used.
Is this caused by the engine, or the hardware I am using? I kinda shudder at the thought that my blits will have a different transparency on each end user device...

Offline EgonOlsen

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Re: Low range of blitting transparency
« Reply #1 on: December 25, 2012, 10:12:10 pm »
That behaviour mimics the behaviour of the hardware renderer of desktop jPCT, which itself mimics the behaviour of the software renderer. It's like it is for historical/compatibility reasons. You can adjust this with http://www.jpct.net/jpct-ae/doc/com/threed/jpct/Config.html#glTransparencyMul and http://www.jpct.net/jpct-ae/doc/com/threed/jpct/Config.html#glTransparencyOffset.
« Last Edit: December 26, 2012, 12:19:29 am by EgonOlsen »

Offline Irony

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Re: Low range of blitting transparency
« Reply #2 on: December 25, 2012, 11:40:00 pm »
Cool! You even work on christmas day :)
thx a lot