Computer Graphics Stack Exchange
Computer Graphics Stack Exchange

Questions tagged [texture]

For questions related to textures: procedural generation, encodings, aspect characterisation, filtering, mapping, storage...

252 questions
16
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How does mip-mapping work with non-power-of-2 textures?

I have heard that recent GPUs all support non-power-of-2 textures and all features just work. However, I don't understand how mip-mapping would work in such a scenario. Can someone explain?
ap_
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11
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1 answer

Algorithms for down sampling an image?

Bicubic sampling is pretty good for up sampling an image and making it larger, but is it a good choice for down sampling as well? Are there better choices?
Alan Wolfe
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11
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2 answers

Are textures automatically Morton-coded when loaded to VRAM?

I know that texture caching on GPU works to optimize locality in 2D (or 3D if using 3D textures). I believe this is done using space-filling curves like Morton or Hilbert curves. When passing an array of texture data to the GPU, though, for example…
russ
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10
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Do you need to use a lowpass filter before downsizing an image?

Apparently bicubic pixel interpolation is good for scaling up or down an image (in real time or not). Is it recommended to use a lowpass filter before downsizing though, or does the bicubic sampling handle aliasing problems at all?
Alan Wolfe
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6
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3 answers

Gaussian blur with transparency

I made a convolution testing program for experimenting with stuff. I've created a 5x5 Gaussian kernel for blurring. Everything looked fine, then I tried to blur a transparent png with a white circle in the middle. On the blurred image, the edge…
Rothens
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4
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1 answer

What happened to my texture mapping?

Recently, I am writing a simple software rasterizer for self-studying and fun. But the texture mapping has problems. The texture I want to map is below: But the final image of two triangles is problematic, it shows below: The triangle rasterizing…
alexunder
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3
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How should the texture file look like?

I am wondering why the texture of the following 3D model https://app.ignitionrobotics.org/GoogleResearch/fuel/models/Transformers_Age_of_Extinction_Mega_1Step_Bumblebee_Figure Looks like the following: https://i.stack.imgur.com/A9Gd0.jpg How are…
Mona Jalal
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2
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2 answers

BC7 texture with alpha has the same size as BC7 without alpha

So i've a made a texture. I've saved the RGB one with BC7 compression, then added alpha channel[specular map] with varying levels of grayscale, and saved the file again as RGBA with BC7 compression. The resulting file has the same size as the one…
Piotr Burzała
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1 answer

Are texture binds expensive?

I am trying to get a feel for how much effort I should put into this. I am building a basic 2D engine and for my use case there are only 8 textures. Each draw call in this engine currently requires that its 1 corresponding texture be bound to '0'.…
J.Doe
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1
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1 answer

Barycentric Coordinates of a Point on a Line

Given a point and a line segment, how do you calculate the barycentric coordinates of the point to the line? bool BarycentricCoordinates(const Vector3& point, const Vector3& a, const Vector3& b, float& u, float& v, float epsilon)
MOJOMO
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Best approach for slicing texture images for raycasting

I'm working on a 2D (pseudo-3D) raycaster which operates on a 2D tile grid. For each ray sent out, the screen draws a rectangle with a certain height depending on the distance between the camera and the wall the ray collided with (like Wolfenstein…
Zoler1337
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compressing my [0,1] floats by throwing away the integer part

I am compressing a string of data in the formats of float. The current approach is throwing away eight bits in the integer part as my float is strictly within [0,1]. I wonder how I could do this.
Lilylilyren
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