How can I get and set pixel data in XNA?

Question

I have a texture2D where I want to get the color of a specified pixel. Do something with it and put a new color in an other texture2D.

I will need to do this with all the pixels in the texture. How can I do this.

No pixel shader's please. It need to be in C#

Isn't that what pixel shader's are for? Why wouldn't you want one? — Nate, Feb 16 '10 at 20:01
How big are your textures? setting data onto a texture isn't too bad but getting data from a texture can be very slow... — Martin, Feb 16 '10 at 23:21
I am trying to do a 2d water animation. Go here:http://freespace.virgin.net/hugo.elias/graphics/x_water.htm. The textures are not very big. I think that they are 400 x 300. I will keep experimenting to see how big I can make them. — Aaron de Windt, Feb 17 '10 at 00:30

score 2 · Accepted Answer · answered Feb 16 '10 at 20:00

2

The Texture2D class contains the GetData and SetData methods that should do exactly what you want.

answered Feb 16 '10 at 20:00

David Brown

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While this will do the trick, depending on what you're doing this can be very, very slow. – Dave Carlile Feb 16 '10 at 22:53
There are samples in the MSDN documentation that I linked to. – David Brown Oct 05 '11 at 04:01
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@dotTutorials: The `GetData` overloads have samples. `SetData` had samples when I posted the comment in 2011. I don't have any control over MSDN. – David Brown May 23 '12 at 17:51
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This is why you should not only answer by linking also give more explanation ;) – Matt Jan 22 '16 at 08:06

score 0 · Answer 2 · answered Feb 17 '10 at 00:27

I found my problem.

When I was trying to get the color of a pixel the Alpha value of the color was 0. This means that the color would be completely transparent. To solve it I just needed to change the Alpha value to 255.

I think that this happened because I am using an jpg file. Jpg file's do not support Alpha values.

How can I get and set pixel data in XNA?

2 Answers2