Draw with alpha channel brush

[sinisrus]

Hello,

I have a problem for draw with alpha channel
If draw with "Doublebuffer and brush hadware=True" => alpha channel bug (only os4, work good on windows and os3.9)
If draw without "Doublebuffer and brush hadware=True" => alpha channel good work (no good for me i prefer use double buffer)

Test my script for see this:
http://amitheme.amiga-ng.org/amiga/test.lha

Run my script, draw and clic on button "SaveBrush" and see "ram:MyProblem.png"

is it a bug??

[airsoftsoftwair]

No, this isn't a bug. You are trying to draw to a hardware brush using combomode 2. This isn't supported for hardware brushes. Hollywood should normally report that this isn't supported. So the only bug here is that Hollywood doesn't report that what you're trying to do isn't supported. I'll fix this.

The reason why it's working correctly on Windows and OS3.9 is that on those systems Hollywood doesn't use hardware brushes.

[sinisrus]

do you have a workaround for the problem?
I would like to make a Painting software with layers

i use the brush hardware and double buffer for very fast painting I miss just transparency

Please can you see if you can find a soution (make new function or other for next release of hollywood or if i use GLGalore for fast painting with transparency???)

PLEASE PLEASE PLEASE !!!!!

[airsoftsoftwair]

First I need to know what exactly you want to do... the code posted is too long and confusing for me to suggest a workaround. Please make it really simple

[sinisrus]

I would like to draw like in ArtEffect, fxpaint, tvpaint ... With transparent brush. In another script I use a Bresenham algorithm is super fast even with huge brush. I use double buffering and hardware brush but I really need transparency.

[sinisrus]

I have updated my script (very short) for you

http://amitheme.amiga-ng.org/amiga/test.lha

[airsoftsoftwair]

I don't know ArtEffect and FXPaint. Can you describe in technical terms or with an image illustration what you mean by "drawing with a transparent brush"?

[sinisrus]

When I draw I use double buffering and hardware brush that is super fast. The problem is that the alpha channel does not work correctly.

See my script run and draw with push left mouse Burton

And look after click the blue button for look the problem of channel alpha

[airsoftsoftwair]

Is it really necessary to use combomode 2 for this purpose? Can't you just use normal combomode?

[sinisrus]

i tested "COMBO_NORMAL" no good for me

My script good work only if disabled the "HARDWARE" brush => but it is too slow

I despair...