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0
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1
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28
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Android Open GL ES2 Incorrect background pixels alpha-blended
Using Open GL ES2 on Android I am rendering textures into a texture and for some insane reason my semi-transparent texels are getting alpha blended with pixels at an offset from the destination pixel. ...
0
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0
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65
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How to find min./max. possible alpha values for perceptually equal resulting color after blending 2 RGBA colors
I have a blending function, that correctly blends an sRGBA foreground color over another sRGBA background color by using premultiplied alpha blending.
blend_premultipy_alpha(srgba_color_foreground,...
0
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1
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126
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Issue With TForm.AlphaBlend and AlphaBlendValue
In my Delphi project, the availability of some features depends on the user's licence. So, a Basic licence will not allow access to Advanced features. However, I want Basic licence users to see what ...
0
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1
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55
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Why is Webgl canvas effected by CSS background?
When I set my body element of background #000, and the circle seems great:
Figure A
However, with unset or #fff background, the color of the edge of this circle seems like calculated with white and ...
0
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1
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204
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OpenLayers: can I get a color which gets by overlaying layers with some opacity?
I have 2 layers with some opacity:
var vectorLayer = new ol.layer.Vector({
source: vectorSource,
style: function (feature) {
return new ol.style.Style({
fill: new ol.style....
2
votes
1
answer
605
views
Fast Alpha Blending (CPU only)
I'm currently optimizing my manual (CPU driven) alpha blending (pixel b over pixel a according to the alpha value of pixel b).
I'm currently using:
uint8_t invAlpha = !Alpha;
uint8_t R = (Alpha * ...
0
votes
1
answer
208
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Why are my blurred drop shadows lightening instead of darkening a semi-transparent color in Pygame?
I feel like there is some fundamental aspect of alpha blending that I'm not understanding here.
I'm doing the following in Pygame to create a blurred drop shadow:
draw a white object
draw a black ...
0
votes
1
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35
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Compositing ARGB Bitmaps Together CPU-only
this is a problem I am facing. When trying to composite several bitmaps together I get a weird result.
Desired result (but this was done manually)
Current result with the weird oddities
This is the ...
1
vote
1
answer
70
views
pixman_image_fill_boxes() does nothing
I am trying to perform alpha blending with pixman_image_fill_boxes().
void blend1(void *di, int p, int w, int h, int r, int g, int b, int a)
{
pixman_color_t color = { .red = r, .green = g, .blue =...
0
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1
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411
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Skia library not able to use alpha masking
I want to achieve alpha masking with two complex shapes with skia.
Shape 1 : Complex draw operating , with multiple canvas save and restore. In the example text("Skia").
Shape 2 : Mask layer,...
0
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1
answer
183
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How overlay a image to specific part on another image in opencv
I have below image and I want to overlay a black patch on the right most side of the image. So I am resizing the both the images to specific size in below code and get only the non white part of ...
0
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1
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71
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webgl2 problem with rendering opaque and translucent triangles
I am working from a sample at https://interactivecomputergraphics.com/. My goal is to have a simple example that shows alpha blending with opaque and translucent triangles. I have 6 squares (2 ...
5
votes
2
answers
168
views
Correct alpha blending parameters in a transparent MTKView?
I've recently tried to create a transparent MTKView where I can draw some geometry, including partially-transparent geometry, and have the results correctly composited with any views behind that ...
1
vote
1
answer
517
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How to overlay images with alpha blending using AVX512 instructions?
I have two images A and B that are stored as byte arrays of ARGB data:
Image A: [a0, r0, g0, b0, a1, r1, g1, b1, ...]
Image B: [a0, r0, g0, b0, a1, r1, g1, b1, ...]
I would like to overlay image B on ...
1
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0
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75
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Processing sketch: merge alpha channel video with another movie
I have a Processing sketch.
I need to overlay a .mov video with alpha channel transparency with another video. The rest of the code works but i got error when the overlay should be started.
I'm afraid ...