Feature #1240
Alpha Blended 8-bit, non-colorkeyed particle images
100%
Description
Is there anyway to tell the engine to use the particle
image
itself for the alpha channel? Color keying won't achieve
a
smooth blend (obviously).
Since the particle is greyscale anyway, there is no need
to
add another 3 color channels just to get the alpha
channel.
In nearly all cases the alpha channel would be exactly
the
same as the image.
It would greatly improve the speed of tex particles if the
same pixel data was used for the alpha blending.
At the moment it requires the particle textures to be
saved as 32bit, when 8bit images could achieve better
quality as the saving could be better invested in higher
res particle textures.
Eg:
64*64 32bit tga = 17kb
64*64 8bit tga = 4kb
And the only difference between the two is the alpha
chanel. The other color channels are redundant.
So as you can see, if the above method was used, we
could double the resolution and see NO slow down at all.
Dani J
Labels: Graphics
History
#1
Updated by skyjake over 21 years ago
Updated by Logged In: YES
user_id=717323
In 1.7.12, particle textures without any alpha data will be
processed in the following way:
1. Calculate averages of the RGB values of all pixels. This
results in an 8-bit grayscale image.
2. The calculated averages become the alpha channel.
3. The pixel colors are all set to white.