GL_REPEAT on a sprite created from frame!

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GL_REPEAT on a sprite created from frame!

(4 posts) (4 voices)

Started 1 year ago by Ozden79
Latest reply from ehoffman

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Ozden79
Member

Hello There,

I looked all around the cocos2d forum as well as web for this but couldn't find any solution so maybe somebody can help me.

I create sprites from a spritesheet using a plist file. For some of those sprites, I want to change their sizes and tile their textures, such as repeating 10 times. I know I've to set texparams that's ok but at the mean time I think I need to change the size of the sprite in order to see the tile effect and that's my problem. How can I change the size of a sprite?

Thanks in advance...

Özden

Posted 1 year ago #
MonkeyBusiness
Member
I am looking to do the same thing. I understand how to make a single png file repeat with the following code:
```
background = [CCSprite spriteWithFile:@"filename.png" rect:CGRectMake(-30, 0, size.width, size.height*10)];
ccTexParams params = {GL_LINEAR,GL_LINEAR,GL_REPEAT,GL_REPEAT};
[background.texture setTexParameters:&params];
```
But since there's no [CCSprite spriteWithSpriteFrame: rect:] method I can't figure out how to repeat a sprite frame over and over to to make an endless scrolling background.
Posted 1 year ago #
lws
Member

You can't, unfortunately. It's the way GL_REPEAT works. It takes a full texture and repeats the full texture.

One thing that might work is to use only one dimension to repeat, i.e. put your sprites all in one row or column on the sheet, having the full width of the row/column. Then you could probably configure it to repeat just horizontally/vertically. There was a thread about this already.

Posted 1 year ago #
ehoffman
Member
The easiest way would be to use multiple sprites within one batch node. Init the batch node with your texture. Add all sprites you want to it, scale some of the sprites, rotate them ... whatever you want/if you want. Then set the position of the sprites such that it looks like "repeating texture".

As it is one batch node, the drawing is very efficient and as it uses the same texture, memory efficient, too. It's almost the same as to manipulate the texture to repeat.

To get this working, you need to split your sprite in multiple "sub sprites". For example you have a square
```
+-----+
|     |
|     |
+-----+
```
And you want 4 repeating textures, do
```
+--+--+
|  |  |
+--+--+
|  |  |
+--+--+
```
Then split every square into two triangles. Set texture coordinates as it's done for the large square (see CCSprite class), but now for every "subsquare".

So easier is to use multiple sprites.
Posted 1 year ago #

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