Alpha blended sprites?

[dogy D.]

Hi everyone.
I am a newbie DelphiX programmer and i started working on my game.
I made a road for the background, and i want to make a water sprite on the road, but it just looks silly being only blue, so I would like to make it kind of transparent (about 60%?)

Is there any way to do this?

[Useless Hacker]

Use the DrawAlpha or DrawRotateAlpha methods to draw the image, passing in a value of between 0 and 255 for the Alpha.

[dogy D.]

Thank you, I'll try that.

[dogy D.]

I did it, but it is very VERY slow.
I tried what I could think of (not much) to speed it up, but still fps goes way down when alphablending. :cry: :evil:
Is there any way to speed it up?

[Useless Hacker]

The trouble is, DelphiX does the alphablending (and rotation) in software, since DirectDraw does not support this in hardware.

You could try creating a combined road/water image initially, then just redrawing that using the normal draw method, but this would only be of use if the image was fairly static.

[dogy D.]

Thanks for suggestion, but it's not static, so I made something else instead of water. Now I would like to make fadein/out effect between levels for my game. I tried AlphaBlending and ofcourse result was very slow. So the question is: How to make fadein/out effect in Delphix?

[Useless Hacker]

Apart from alpha blending, you can use gamma ramps or palette animation.
Palette animation is only available if you are using 8-bit or less colour, but there is a sample in the DelphiX package showing how to do this.
Gamma ramps are rather more complicated, though Alimonster wrote an article about how to do it in straight DirectDraw (here).

[dogy D.]

Thank you for your help.

[Finch]

Try PowerDraw (http://turbo.gamedev.net/powerdraw.asp). PowerDraw can draw TGA images, which support transparency, and does it in hardware, because it uses DirectX 9.