Need suggestion for multiple lines

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I try to create a line chart. I use a camera and a render texture. I show that chart on UI using raw image. When I disable chart generator script I get 120 fps. When I enable it I have 30 fps. I have i9-9900K and 2080 Ti. There are 200 disc and 200 lines on my chart. I tried enable and disable GPU Instancing.


How can I optimize performance?

Image 672

Image 673

Reporting a bug? please specify Unity version:
2021.3
Reporting a bug? please specify Shapes version:
4.1.1
Reporting a bug? please specify Render Pipeline:
URP
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Freya Holmér creator
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this is slow because you're alternating between lines and discs (ie, each iteration draws a line, and then a disc, which prevents GPU instancing). To save performance, you should draw all lines first, and then all discs.

another optimization would be to use a polyline instead of individual lines, and only recalculate the polyline when the lines change shape, instead of on every draw. There's more information on performance optimization in the shapes docs

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Freya Holmér creator
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  • Answered

this is slow because you're alternating between lines and discs (ie, each iteration draws a line, and then a disc, which prevents GPU instancing). To save performance, you should draw all lines first, and then all discs.

another optimization would be to use a polyline instead of individual lines, and only recalculate the polyline when the lines change shape, instead of on every draw. There's more information on performance optimization in the shapes docs

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atmuc
Quote from Freya Holmér

I'm a little but confused, these look like horizontal lines, not a line graph, and I don't sere the discs in this code

I did not share whole code.

Draw.Thickness = LineThicknessData;

var start = Vector3.zero;
var end = Vector3.zero;

start.x = (Data1[0].x * pixelPerUnitX) - halfWidth;
start.y = (Data1[0].y * pixelPerUnitY) - halfHeight;

for (int i = 1; i < Data1.Count; i++)
{
end.x = (Data1[i].x * pixelPerUnitX) - halfWidth;
end.y = (Data1[i].y * pixelPerUnitY) - halfHeight;

Draw.Line(start, end, Color1);

if (DrawPoints)
{
Draw.Disc(start);
}

start = end;
}

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atmuc

Draw.Polyline performance is better but the result is not good.

Image 675

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Freya Holmér creator

I'm a little but confused, these look like horizontal lines, not a line graph, and I don't sere the discs in this code

Avatar
atmuc

public override void DrawShapes(Camera cam)

{

using (Draw.Command(cam))

{

Draw.LineGeometry = LineGeometry.Flat2D;
Draw.ThicknessSpace = ThicknessSpace.Pixels;
Draw.Thickness = LineThicknessMajor;
Draw.Matrix = transform.localToWorldMatrix;
Draw.Color = Color.blue;

for (int i = 0; i < lineCountMajorY; i++)
{
var y = -halfHeight + i * StepMajorY * pixelPerUnitY;
var start = new Vector3(-halfWidth, y, 0);
var end = new Vector3(halfWidth, y, 0);
Draw.Line(start, end, Color.black);
}

}

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Freya Holmér creator

how are you generating/drawing the charts right now?