alphablending

A newbie question I have this layers.xml that I use as a source for an ImageView. And two images, mask.png and image.jpg layers.xml: <layer-list xmlns:android="http://schemas.android.com/apk/res/android"> <item> <bitmap android:src="@drawable/image" android:gravity="center"/> </item> <item> <bitmap android:src="@drawable/mask" android:gravity="center"/> </item> </layer-list> ImageView: <ImageView android:id="@+id/img_B" android:layout_width="fill_parent" android:layout_height="fill_parent" android:src="@drawable/layers"/> At the moment the output is just the png over the image. I would like

I am rendering to a texture through a framebuffer object, and when I draw transparent primitives, the primitives are blended properly with other primitives drawn in that single draw step, but they are not blended properly with the previous contents of the framebuffer. Is there a way to properly blend the contents of the texture with the new data coming in? EDIT: More information requsted, I will attempt to explain more clearly; The blendmode I am using is GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA. (I believe that is typically the standard blendmode) I am creating an application that tracks mouse

How do I replace the alpha channel of any image (png, jpg, rgb, rbga) with specified background color? It must also work with images that do not have an alpha channel. This can be done by checking if the image is transparent def remove_transparency(im, bg_colour=(255, 255, 255)): # Only process if image has transparency (http://stackoverflow.com/a/1963146) if im.mode in ('RGBA', 'LA') or (im.mode == 'P' and 'transparency' in im.info): # Need to convert to RGBA if LA format due to a bug in PIL (http://stackoverflow.com/a/1963146) alpha = im.convert('RGBA').split()[-1] # Create a new background

I am trying to do an alpha blend operation of an RGBA image (foreground image), on to a RGB image (background image). However, while doing so I think I may be doing the wrong alpha blending operation or doing it wrong. For example, the pixel of my RGB image is a grayish color of (127, 127, 127). The pixel of my RGBA image for the pixel will be (0, 0, 255). After I do my blending operation, the final color will be (127, 0, 255). However, I thought that was more of an additive blend and different than the operation I am doing. For how my values are set, take a look at this incPixelColor[0] = 0;

I'm trying to gauge the possibility of a patch to WebKit which would allow all rendered graphics to be rendered onto a fully transparent background. The desired effect is to render web content without any background at all, it should appear to float over the desktop (or whatever is displayed behind the browser window). Has anyone seen an app do this? (I can think of some terminal emulators that can.) If anyone has worked inside of WebKit (or possibly Gecko?) do you think it would be possible to do this? Update: I've come to realize that Mac OSX dashboard widgets use this exact technique. So,

I am trying to create a heat map with gradients that look similar to this: This image shows three points and the gradients blend nicely together. Here is what I am currently doing in my drawing function: public void DrawGradient(int x, int y, Graphics g) { using (var ellipsePath = new GraphicsPath()) { var bounds = new Rectangle(x, y, 100, 100); ellipsePath.AddEllipse(bounds); var brush = new PathGradientBrush(ellipsePath); Color[] colors = { Color.FromArgb(64, 0, 0, 255), Color.FromArgb(140, 0, 255, 0), Color.FromArgb(216, 255, 255, 0), Color.FromArgb(255, 255, 0, 0) }; float[]