cocos2d for iPhone

A fast, easy to use, free, and community supported 2D game engine

1. 

   mtran003
   Member

   Back in the old days when I was programming for the Amiga using AMOS Pro (yes, I am that old), it was possible to affect a color for the entire screen, by changing the color values of a single color index. For example, if I wanted to simulate a night time lighting sky, I would change the color index used for the sky (usually color 0) and change the color value from black to white and back again. Or I could write a loop to smoothly transition between two colors. And it was fast. No performance hit at all.

   Is such a thing possible for iPhone/Cocos2d?

   I realize such a thing is *theoretically* possible, using sprite fades or in the extreme case--even sprite animation. But the area I need to affect can be very large and not always the same size or shape and is always changing in run time. As usual, performance is king.

   Does anyone in this community have and ideas how to go about doing this? Any articles or tutorials?

   Regards,
   Manny

   Posted 1 year ago #
2. 

   max9xs
   Member

   @mtran003 : Use CCcolorLayer like

   CGSize s = [[CCDirector sharedDirector] winSize];
   CCColorLayer* layer = [CCColorLayer layerWithColor: ccc4(0xFF, 0x00, 0x00, 0x80)
   width: 200
   height: 200];
   layer.isRelativeAnchorPoint = YES;
   layer.position = ccp(s.width/2, s.height/2);
   [self addChild: layer z:1 tag:kTagLayer];

   Posted 1 year ago #
3. 

   max9xs
   Member

   Visit it,

   http://www.cocos2d-iphone.org/api-ref/0.9.0-alpha/interface_c_c_color_layer.html

   Posted 1 year ago #
4. 

   fabiorodella
   Member

   In the old days, that was possible since the screen was palette-based (color depth < 8 bit), so if you changed a color in the palette you also changed the entire screen. I'm not sure if you can use (or simulate) 8-bit screens on the iPhone, but I'll let someone more enlightened confirm this :)

   Posted 1 year ago #
5. 

   christophersisk
   Member

   In effect it would be possible to emulate using modern methods (rewriting a texture every update based on the palette info stored in a variable for instance), but to my knowledge there is no way to gain the speed gains from true color cycling like on old hardware.

   Basically hardware has moved on from the days of 8-256 colors, and the hardware support for limited palette techniques have (sadly?) died out.

   Posted 1 year ago #
6. 

   fabiorodella
   Member

   You used to be able to have some pretty cool and cheap effects using palette rotation, that is what I miss the most :)

   Posted 1 year ago #

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