Computer Graphics Stack Exchange
Computer Graphics Stack Exchange

Questions tagged [scanline]

8 questions
14
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3 answers

What is "Scanline Racing"

I've heard a lot of people working on VR talk about scanline racing and that it's supposed to help improve latency for motion-to-photon. However, it isn't clear to me how this can be done with OpenGL. Could someone explain how scanline racing…
Mokosha
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2 answers

Is there some kind of Bresenham algorithm or equivalent for scanline rendering a rotated ellipse?

Back in the day when you often had to write your own low level rendering algorithms we all used to learn the Bresenham algorithms for lines and circles. It was almost trivially easy to extend the Bresenham circle algorithm to cover ellipses whose…
hippietrail
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6
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1 answer

Why is the scan line filling algorithm so seemingly over complicated?

It makes use of tables, buckets, and sorting, which all seem unnecessary. I don't understand why I can't just fill between pairs of scan line intersections, ignoring vertices and edges with gradient 0. My lecturer didn't provide the best notes on…
toastedDeli
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2
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0 answers

Scan Line Polygon Fill Edge Table Entry Order

I am trying to figure out the correct order between edges on edge table on scan line polygon fill. One example here on Y=1 takes first AB line And another example takes on Y=0 v1v0. I cannot understand why not AB instead of BA and why v1v0 instead…
valkon
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2
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1 answer

A solution to sprite visibility in a raycasting engine with variable wall heights?

I am writing a raycasting engine. At this point, I have added sprites, and I am using a z-buffer, with one stored length to a wall for the x coordinate of each ray. Below is an image of a sprite which is fully visible. Z-buffering works fine when…
Caspian Ahlberg
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How to do a scanline fill with a self intersecting polygon?

I have a bezier curve and would like to draw it's stroke. To do that, I planned to approximate the stroke to a polygon and fill it with a scanline algorithm. While I feel confident about implementing the conversion and the scanline algorithm, I am…
Julius
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1
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1 answer

Is drawing Bezier curve with scanline algorithm possible with Vulkan?

As an information, Vulkan is a low-level abstraction layer thru modern GPU. It allows programmers to program the GPU and assemble rendering pipeline. On that pipeline, there are modules of program which are called "shaders". As a programmer, we only…
Thor-x86_128
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How to make sure that triangles share edges (also not overlap each other) when rendering a quadrilateral?

Here is my simple scanline-based triangle rasterizer using pure integer arithmetic. I adapted the code from this Stack Overflow answer The below code attempts to render a coloured quadrilateral by rendering two triangles. /* g++ trig.cpp -o trig…
Jimmy Yang
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