gradient

I'm trying to interpolate between two colours in HSV colour space to produce a smooth colour gradient. I'm using a linear interpolation, eg: h = (1 - p) * h1 + p * h2 s = (1 - p) * s1 + p * s2 v = (1 - p) * v1 + p * v2 (where p is the percentage, and h1, h2, s1, s2, v1, v2 are the hue, saturation and value components of the two colours) This produces a good result for s and v but not for h. As the hue component is an angle, the calculation needs to work out the shortest distance between h1 and h2 and then do the interpolation in the right direction (either clockwise or anti-clockwise). What

Microsoft provide an excellent SVG gradient maker so IE9 can also have "CSS3" gradients (click Custom). I currently utilise their logic for my Fireworks and Dreamweaver extensions to convert gradients to SVG, but I only know how to do it for standard top, bottom, left, right directions. If you enter an angle, I don't do the conversion, because I'm not sure how I would convert x1, x2, y1, y2 to CSS3 angle degrees. The gradient generator provides values like this: x1="0%" y1="0%" x2="56.262833675564686%" y2="68.29999651227678%" I'm not great with mathematics or trigonometry, so could somebody

I want to implement alpha gradient on an image. From 0.5 alfa on top of the image to 0.0 on bottom. Any advice, tutorial, link is welcome. You can use CGImageCreateWithMask to apply a masking image to it. You could generate an appropriate mask simply enough by drawing to a greyscale or alpha-only CGBitmapContext with CGContextDrawLinearGradient . If it's being displayed as the content of a CALayer, you could apply an appropriate masking layer to the parent layer's mask property. You could use a CAGradientLayer with appropriate colors to create this mask. You can draw the image to a

How to animate gradient from color#1 to color#2? Something similar to I'm planning to use it as health-bar for unit (so, it will be finit animation starting with green and ending with red) Nexen While googling it, I found 2 ways to do it for android: use ShaderFactory or extends View, using new Shader(new LinearGradient()) . Both answers do the same - calling new Shader() every View.onDraw(Canvas canvas) method's call. Its really expensive if number of such animated gradients more than ~3. So I did it another way. I avoided calling new every onDraw() , using single precalculated LinearGradient

I'm working on creating fancy looking UIbuttons by adding linear gradient to the button. However I'm not sure at which index I need to add the gradient. The code that I have currently places the gradient over the image/text. How can I insert a sublayer to a UIButton under the text/image sublayer? It is important for me to keep the text and the image of a button visible! +(void)addLinearGradientToView:(UIView*)view TopColor:(UIColor*)topColor BottomColor:(UIColor*)bottomColor { for(CALayer* layer in view.layer.sublayers) { if ([layer isKindOfClass:[CAGradientLayer class]]) { [layer

There are a few similar questions on the site, but I'm looking for something specific and slightly different. I followed the direction given here: http://www.cimgf.com/2010/01/28/fun-with-uibuttons-and-core-animation-layers/ to subclass UIButton in order to create a generic class that I can specify the gradient colors on, rather than trying to use a static image. I ran into a problem where the setMasksToBounds on the button's layer would either allow A) the drop shadow to show, but also allow the gradient layer to show beyond the rounded corners OR B) the gradient layer to clip to the rounded