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Questions tagged [alphablending]

Alpha blending is a convex combination of a translucent foreground color with a background color allowing for transparency effects.

562 questions
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Windows Forms: Making a cursor bitmap partially transparent

I want to use partially transparent images in drag/drop operations. This is all set up and works fine, but the actual transformation to transparency has a weird side effect. For some reason, the pixels seem to be blended against a black background.…
Pedery
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OpenCV (Emgu.CV) -- compositing images with alpha

I'm using Emgu.CV to perform some basic image manipulation and composition. My images are loaded as Image. Question #1: When I use the Image<,>.Add() method, the images are always blended together, regardless of the alpha value. Instead…
roufamatic
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ImageList promises me Alphablending, but how do I enable it?

I want my buttons to have images with alphablending on them. As instructed I've included a TXPManifest component on my mainform. Below are some images I've loaded into my project. However my BitBtn, which is linked to the imagelist via an…
Johan
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iOS: simple animation

I want to create a simple animation changing alpha value: [UIView beginAnimations:nil context:NULL]; [UIView setAnimationDuration:2]; [view1 setAlpha:0.00]; [UIView commitAnimations]; Ok in this way I change the alpha value for two seconds and it…
cyclingIsBetter
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Discoloration in OpenGL

I'm using OpenGL to draw in 2D. I'm trying to overlay textures with alpha. I have done this: glDisable(GL_DEPTH_TEST); glDepthMask(GL_FALSE); glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA); glEnable(GL_BLEND); And then I draw in reverse z-order.…
andyvn22
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Webgl does not have an alpha background channel on ios safari

I set up a webgl canvas on my page, and used these params at startup: gl = canvas.getContext("webgl", { alpha: true, premultipliedAlpha: false }); Then I did all the setup work to make a program, a vertex shader and a fragment shader. My…
YAHsaves
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iPhone opengl es alpha-blending. I have black color in edge

I am developing iPhone game. I have the below Source image to draw it to the background. The Source image has alpha 0x00 and gradation around edge and the background's alpha is 0xff. When I draw the source image to the background, I have black color…
mooongcle
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SDL2 - Draw fully-transparent circle on a texture

I'm developing a 2D game in SDL 2.0 and I'm having am trouble with my lighting system. I want to fill the screen with fog and create a transparent circle around the player (lower-left). I know how to make a dark room with a tinted light using…
DragonDePlatino
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How do I draw an image with an alpha channel to a TSpeedButton?

I've got a TSpeedButton, and a TImageList that holds various glyphs. One of them has an alpha channel, and it looks very nice when drawn to certain parts of the UI... but when that glyph is drawn on a TSpeedButton, it doesn't take the alpha channel…
Mason Wheeler
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Variable alpha blending in pylab

How does one control the transparency over a 2D image in pylab? I'd like to give two sets of values (X,Y,Z,T) where X,Y are arrays of positions, Z is the color value, and T is the transparency to a function like imshow but it seems that the function…
Hooked
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HTML5 Canvas Creative Alpha-Blending

So I have an animation that I'm coding in javascript and HTML5 (no libraries, no plugins, no nothing and I'd like it to stay that way). The animation uses physics (basically a bunch of unusual springs attached to masses) to simulate a simple liquid.…
mindoftea
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Change Alpha Blend Mode in WPF?

The System.Drawing.Graphics class has a property CompositionMode with two options: SourceOver (which, based on the alpha component, blends whatever is drawn with the background already existing) or SourceCopy which simply overwrites the background…
Harald
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OpenGL ES (IPhone) alpha blending looks weird

I'm writing a game for IPhone in Opengl ES, and I'm experiencing a problem with alpha blending: I'm using glBlendFunc(Gl.GL_SRC_ALPHA, Gl.GL_ONE_MINUS_SRC_ALPHA) to achieve alpha blending and trying to compose a scene with several "layers" so I can…
Damian
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android/opengles alpha textures not semitransparent but binary transparent

I am drawing some textures with alpha channel, but when they are displayed it looks like the alpha channel is only binary. So a pixel is either transparent or opaque, although in the texture file itself the pixel is half-transparent. The blending…
clamp
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Is it possible to create a CImageList with alpha blending transparency?

I would like to knwo if it is possible to create a CImageList with alpha blending transparency. Sample code that creates a CImageList with ugly transparency (no alpha blending) CGdiPlusBitmapResource…
sorin
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