cocos2d for iPhone

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

1. 

   rbrooky
   Member

   I hope anyone can point me in the right direction. I'm trying to get an effect where the background fades away into darkness. To achieve this I created a gradient in Photoshop from black to transparent and stored this as a PNG file. I then use this gradient to lay over the background in my game expecting the transparent part to show the background file (also PNG) and the black part to cover it entirely and in between it slowly fades from transparent to black.

   The problem is that the complete tranparent part of the gradient works fine, the none-transparent part (black) as well but in between there is a white semi transparent section. I would like to add a screen shot here but I don't know how to post a picture.

   The background is moving from left to right so I can't create the whole background in Photoshop.

   Appreciate any help I can get.

   Posted 2 years ago #
2. 

   dbolli
   Member

   Are you defaulting to 32 bit pixel format as per the FAQ entry
   "My PNG doesn't look like in Photoshop"?

   [[Director sharedDirector] setPixelFormat:kRGBA8]; // Default is RGB565
   [Texture2D setDefaultAlphaPixelFormat:kTexture2DPixelFormat_RGBA8888]; // Default is RGBA8888

   Regards,
   Derek.

   Posted 2 years ago #
3. 

   rbrooky
   Member

   Yes, I am. I'm doing that in the AppDidFinishLaunching method:
   - (void)applicationDidFinishLaunching:(UIApplication *)application {

   UIWindow *window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
   [window setUserInteractionEnabled:YES];
   [window setMultipleTouchEnabled:YES];
   [[Director sharedDirector] setPixelFormat:kRGBA8];
   [Texture2D setDefaultAlphaPixelFormat:kTexture2DPixelFormat_RGBA8888];
   [[Director sharedDirector] setLandscape: YES];
   // [[Director sharedDirector] setDepthBufferFormat: kDepthBuffer16];
   [[Director sharedDirector] attachInWindow:window];

   // display FPS (useful when debugging)
   [[Director sharedDirector] setDisplayFPS:YES];

   [window makeKeyAndVisible];

   MenuScene * ms = [MenuScene node];

   [[Director sharedDirector] runWithScene:ms];

   }

   And in my game scene I just add the sprite with the gradient:

   Sprite *gradient = [Sprite spriteWithFile:@"Gradient.png"];
   gradient.position = ccp(240, 160);
   [self addChild:gradient z:2];

   I also tried to add the sprite in the following way:
   //Add gradient
   [Texture2D setDefaultAlphaPixelFormat:kTexture2DPixelFormat_RGBA8888];

   Sprite *gradient = [Sprite spriteWithFile:@"Gradient.png"];
   gradient.position = ccp(240, 160);
   [self addChild:gradient z:2];

   // remove texture from texture manager
   [[TextureMgr sharedTextureMgr] removeTexture:gradient.texture];

   //Restore default after adding
   [Texture2D setDefaultAlphaPixelFormat:kTexture2DPixelFormat_Default];

   Both did not have the desired result.

   Is there anything I could do using blendFunc? If so, I have no idea how to use it...

   Thanks for your help!
   Regards

   Posted 2 years ago #
4. 

   rbrooky
   Member

   OK, nevermind. It was completely my own fault and nothing today with Cocos2d. The gradient I created in photoshop had a white transition in it....

   Posted 2 years ago #

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