Hi again,

Its quit cool, but I'm not that good when it comes to do two things at
the same time ;o)

I can't see anything strange when rotating the player-sprite.

Cheers, FROGGS.

Am 23.04.2012 20:46, schrieb Tobias Leich:
> Hi Andreas,
> Am 23.04.2012 09:53, schrieb Andreas Lund:
>> Hi,
>> Running Strawberry Perl on Win 7 x64 I have installed SDL and Alien::SDL from
>> CPAN (selecting option 1) and I'm writing a twin stick shooter game for fun. 
>> I
>> have three questions:
>> 1) When rotating sprites using the ->rotation() method the sprites often get 
>> a
>> line of "artifact noise" along one of the sides, usually the right and/or
>> bottom edge of the original sprite. The effect is not constant and the
>> original sprites are all 100% transparent at the edges so I believe the
>> artifacts are introduced by the rotation algorithm. Or is it?
> Do you have a screenshot? I just can think of problems when
> anti-aliasing and transparency come together...
>> 2) After experimenting with different sprite sizes, it seems that there's a
>> limit somewhere. When attempting to load a sprite that's too large, I get a
>> seemingly valid sprite object that just doesn't seem to render anything. Is
>> there a known size limit to sprites or could this be a driver issue? Or am I
>> overlooking something?
> See http://sdl.perl.org/SDL-GFX-Rotozoom.html, I believe width+height
> must be less than 16384.
>> 3) How exactly does the 'alpha_key' property work? I tried setting it to the
>> ubiquitous bright purple (FF00FF) but this just caused half my sprites to
>> become completely invisible. When using PNG files with an alpha channel, 
>> using
>> a key color seems pointless to me, which makes the POD example code somewhat
>> confusing:
>>     # spawning can include almost all of the above:
>>     my $sprite = SDLx::Sprite->new(
>>               image   => 'hero.png',   # or surface => SDL::Surface
>>               rect    => SDL::Rect,    # or x => $x, y => $y
>>               clip    => SDL::Rect,
>>               alpha_key => SDL::Color, # or [$r, $g, $b]
>>               alpha     => 1,
>>               rotation  => 45, # degrees
>>          );
> Ya, alpha and blitting is not the easiest things as someone might think.
> If you have a png file with alpha channel, and applying an alpha color
> key to it should reset the alpha channel. At least that is what I would
> expect.
> You cant mix the alpha channel and alpha key.
>> If anyone is interested in a sneak peek, here's the code:
>> http://floyd.atc.no/Programming/Perl/IfItMoves/2012-04-23.zip
> Will have a look then ;o)
> Cheers, FROGGS
>> Suggestions are welcome :-)
>> --
>> Andreas Lund (fl...@atc.no)
>> Tel: +47 90077162
>> #include <disclaimer.h>
>> "Look at you hacker, panting and sweating as you run through my corridors.
>> How can you challenge a perfect immortal machine?" -- SHODAN, System Shock

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