Alpha blending is a convex combination of a translucent foreground color with a background color allowing for transparency effects.
Questions tagged [alphablending]
562 questions
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textures with transparent background by using alpha blending opengl
I have scar textures and I want to get rid of the background skin colour by using alpha blending. However, I have problems with changing the opacity of individual pixels of specific textures. What is the easiest way to have textures with transparent…
user3369407
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glBlendFunc and framebuffer object
Alpha blending is not working as expected when I draw to a framebuffer object. Specifically, calling glBlendFunc has no effect on what pixels are in the framebuffer. I check what is in the framebuffer before and after drawing using glReadPixels. The…
Little Endian
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OpengGL Light Blending
I am writing a Lights/Shadows system for my game using Java alongside the LWJGL. For each one of the Light-Emitting Entities I generate such a texture:
I should warn you that these Textures are full of (0, 0, 1) or (1, 0, 0) pixels, and the…
Thiago
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Win32 C++ Alphablend a Bitmap Partially Transparent
I've googled, seen examples, other questions here, MSDN and Downloaded Example code. I cannot figure out what is wrong with this.
// setting up the memory DC and selecting in the bitmap
HDC hdc = GetDC(hWnd);
HDC hdcMem =…
Evan Carslake
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opengl blending only working for one frame
I'm trying to darken my display by drawing a fullscreen black quad, but with only 0.5 alpha. the first frame I render, this works correctly, however after the first frame I only get a black screen.
There's a lot of rendering going on, but here's…
zacaj
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Alpha Blend if Background Alpha is not 255/1.0f
I am trying to do an alpha blending in c#.
So my actual code for this is:
final.Red = (pencil.Red * pencil.Alpha) + (background.Red * (1.0f - pencil.Alpha));
final.Green = (pencil.Green * pencil.Alpha) + (background.Green * (1.0f -…
user3000289
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Android - OpenGL-ES-2.0 alpha blending with ZOrderOnTop
My problem is the following: I am displaying a GLSurfaceView with ZOrderOnTop set to true and with a simple Yellow background.
Sipka
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How can I render back to front in opengl?
I am trying to render an transparent object in opengl but sometimes the textures are visible through each other and sometimes they are not. As far as I know I have to render them from the back to the front and it is looking fine when I do it…
Busti
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C++ DirectX 9.0 Sprite Alpha Blending Not Showing
EDIT: SOLVED
The problem was me using the renderstate functions I needed for alphablending outside of the Sprite->Begin() and Sprite->End() codeblock.
I am creating my own 2D engine within DirectX 9.0. I am using sprites with corresponding…
user3001604
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transform single channel of BitmapData object
I have a BitmapData object with an alpha channel. I'd like to know the fastet way to offset that alpha channel in ActionScript3 (FlashPlayer10). By offsetting I mean shifting all pixels of that channel in one direction (wrapping around the image…
BuschnicK
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OpenGL ES multi-texture alpha blending question
This maybe a noob question, however, I haven't been able to find a suitable answers:
I have an object in OpenGL ES (in fact, an UV mapped export from Blender) and I'd like to apply two textures to it. To be precise, I have a earth-like sphere and I…
zero0cool
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How to achieve D3D output with premultiplied alpha for use with D3DImage in WPF?
We are using a D3DImage in WPF to display partly transparent 3D content rendered using Direct3D on a background which is created in WPF. So, we have something like this:
…
gehho
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glPoint Alpha Blending issue
I am having issues alpha blending glPoints. The alpha blending works correctly when the glPoint is over the background but when a glPoint overlaps another glPoint the background color is visible rather then the underlying glPoint.
// create…
user346443
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Blending problems (OpenGL)
A have a question, maybe someone can help me.
I am trying to make a mirror effect using OpenGL. I draw a transparent plane, a "reflected" scene cut by stencil, and an original one.
But I have a completely non-transparent "wall" instead of the…
Irene
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I need an SSE shuffle routine to avoid negative numbers in a parallel subtraction
I'm working on an SSE2 implementation of an RGB565/RGB555 Alpha Blend and I've run into an issue I haven't been able to wrap my head around. This is the Alpha Blend in C++:
#define ALPHA_BLEND_X_W(dst, src, alpha)\
ts = src; td = dst;\
td =…
user2645004
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