How to increase the brightness of a sprite or set sprite color to ccWHITE?

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How to increase the brightness of a sprite or set sprite color to ccWHITE?

(12 posts) (8 voices)

Started 1 year ago by neophit
Latest reply from vinhsteven

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neophit
Member

I am trying to increase the brightness of a sprite. My assumption was that CCTintTo or CCTintBy could be used to increase the RGB values so they are closer to white (255,255,255). For testing, I used the ActionTint sample in ActionsTest.m.

I modified line 437 to:
id action1 = [CCTintTo actionWithDuration:2 red:255 green:255 blue:255];
There is no visible change to the sprite. It appears that (255,255,255) is not white, but rather the sprites normal color.

I also tried adding:
[tamara setColor:ccWHITE];
No visible change to the sprite.

The documentation doesn't mention anything about this behavior for CCTintTo, CCTintBy, or setColor. Am I doing something wrong or is this a bug?

Cocos2d version: 0.99.1 r1875.

Posted 1 year ago #
pabloruiz55
Member

What you could try is adding a white image below your sprite and reduce your sprite opacity

Posted 1 year ago #
Webtopia
Member

I'm not sure, there may be a bug in your code.

I've used

[CCTintBy actionWithDuration:0.1f red:-255 green:0 blue:0],

to get a bitmapfontatlas to change from red to black. It works fine.

Experiment with CCTintBy and see if you can remove some component of colour first. I haven't used CCTintTo

Posted 1 year ago #
neophit
Member

@pabloruiz55, yeah that would probably work, but I'd like to find a more elegant solution.

@Webtopia, the original line of code in the ActionTint sample is:
id action1 = [CCTintTo actionWithDuration:2 red:255 green:0 blue:255];
The sprite is tinted a purple-ish color as expected.

CCTintTo and CCTintBy are both capable of removing color from an image, but do not appear to be able to add color.

Posted 1 year ago #
greyhoundgames
Member

255,255,255 means normal color on a sprite. You would have to do something else to make the sprite more white. You can put for example a transparent overlay, or do as the above person suggested. I think adding a transparent overlay makes more sense however if your sprite is odd shaped your overlay has to match it or you will get some of the stuff around it to also start changing color. A more advanced technique might be to go into the texture in memory and change the RGBS to be more white or something like that using a render texture.

Posted 1 year ago #
randomtruth
Member
I would have the original sprite be the white version, and change the color of the sprite anywhere you need it not to be white using this code
```
sprite.color = (ccColor3B){redColor,greenColor,blueColor};
```
Posted 1 year ago #
Techy
Member

I think you can also do: sprite.color = ccc3(red,green,blue);
At least thats what I remember

Posted 1 year ago #
neophit
Member

Thank you guys for the input. I'll probably go with an overlay image.

Does anyone know why (255,255,255) is normal color on a sprite?

Posted 1 year ago #
Clain
Member

Because when you set the color of a sprite, you don't modify its R, G and B values. What you modify is the amount of R, G and B that you want your sprite to keep.

If you think in percentages, it's easier to understand. (255, 255, 255) would be (100%, 100%, 100%) and it means that you want the sprite to display its red channel at 100%, its green channel at 100% and its blue channel at 100%. Hence the sprite displays normally.

If you'd change the color to (255, 0, 0), that is to say (100%, 0%, 0%), then the sprite would only display its red component. The green and blue values would be zeroed.

This is also why, if your sprite is originally white (R=255, G=255 and B=255), setting its color property has the same result as if you'd change its real color.

Posted 1 year ago #
greyhoundgames
Member

With the white sprite idea, your sprite will have no contrasts... Are you talking about doing a bright version instead of a white version and then just pulling down the colors as needed?

Posted 1 year ago #
neophit
Member

@Clain, thanks for the explanation! That makes perfect sense. It would be nice if those details were included in the documentation.

@greyhoundgames, I will be using a white sprite with low opacity to achieve the desired effect.

Posted 1 year ago #
vinhsteven
Member

Here is my solution to create a flash effect of Object (i.e when enemy was attacked). My object is an AtlasSpriteManager.

I call method first:
[self setBlendFunc: (ccBlendFunc) { GL_SRC_ALPHA, GL_ONE }];

when I want to finish effect, call method:
[self setBlendFunc: (ccBlendFunc) { GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA }]; //restore normal state.

Posted 1 year ago #

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