Texture or pixel coordinates missing?

[pixelgrip]

I wanted to make a simple graph visualisation in the compositing.Unfortunately in the compositing there is no Texture coordinate node which is needed to get the functions plotted to the pixel coordinates as x and y like we do with shading.

Have i overseen something is there a method to get the texture coordinates or another way for x,y plotting?

Without visualization its almost impossible to adjust gaussian bell curves like this.

[DNorman]

You would probably be better off compositing them from a different scene with alpha over and the same camera resolution settings as the main scene. (could be an orthographic camera)
You only need it to have the same pixel ratio.

[pixelgrip]

The graph is needed because i want exact the same gaussian bell function visualized.
I have builded the bell node function in the compositing for a greater tonemapping function.
The bell curves have min max and deviation values that can be adjusted in realtime.For this reason the plotting is needed in the compositing.

[DNorman]

I have no idea how you are going about this but have you looked into the “Map UV” node (needs a UV pass maybe of a plane that fills an orthographic camera)? I have never used it but it sounds promising.

https://docs.blender.org/manual/en/latest/compositing/types/transform/map_uv.html

It is the only node I can think of that gets UV’s in the compositor for mapping images.

[pixelgrip]

Thanks,could maybe work.I found a tutorial,unfortunately the add texture in the texture editor are greyed out.(Blender alpha)

How to get the render pixels coordinates in compositing

[Joel_RVC]

you could use the viewport compositor (if you want to see it in real time), a plane in front of the camera, add an AOV with the uv output of the geometry node and use that in the compositor.

[DNorman]

@pixelgrip

I found a tutorial,unfortunately the add texture in the texture editor are greyed out.(Blender alpha)

If you select any object in the scene and go into texture paint mode the texture tab will appear by magic and you can then add a new brush texture.

Set the type to none and then open the texture node editor. select Brush as texture type and activate use nodes.

You can exit texture paint mode.

You can now change the nodes (no longer greyed out) and use that brush texture in the compositor as in the tut.

CDMJ was also complaining that texture creation is now bound to brushes I think they managed to persuade the devs to work on enabling access to the old texture nodes directly in compositor but it is very recent and I think not yet implemented. For the moment you have to make a brush.

See this thead (watch this space for progress.)

Global Textures - Blender Render Legacy

They were kind enough to post a fix for now that will enable us to access the blender render textures in the texture node of the compositor. I’ll have to wait for a build to try. Problem is that the procedurals are always live until sent to render and as you adjust brush or shader they update. Main issue I have is access across blender overall. Try a displace texture and that updates as you change the texture same as for a brush. I’m just sure that eventually we will see a more unified system o…

[pixelgrip]

@Joel_RVC

you could use the viewport compositor (if you want to see it in real time), a plane in front of the camera, add an AOV with the uv output of the geometry node and use that in the compositor.

Interesting idea thanks.

@DNorman

If you select any object in the scene and go into texture paint mode the texture tab will appear by magic and you can then add a new brush texture.

Ok i have to select a object,thanks.

Even if one of the ideas are working,this is not tonemapping friendly.As you know i want to load a image in the compositing tonemapper without any object setup if that makes sence.
I wonder why we dont have a simple texture coordinate in the compositing ?

My idea was something like this

Math Graph Shader

Hi Everyone, Not 100% sure if this is the right category, but I wanted to share something I put together a little while ago for graphing math functions in Blender because sometimes it can be handy to actually visualise the transfer function of a shader node instead of its material output [image] It’s fully procedural and comes with adjustable axis lines and tick marks [image] Ever wondered what the transfer function of the “Ease” option of the colour ramp looks like? [image] [image] M…

or this

Math function plotter inside blender

Hi all ! It’s been ages i say i need a math func drawer in blender for monitoring curves, response and anything in a curve drawing way according to shaders. Some years ago, i made one in unity3D but never took the time to do it in blender. Now it’s done And it’s pretty handy ! and simple ! [image] The plane displayed is 20x20 ( -10 to +10 in all axes ) and it allows to display any func in this domain. if you need a wider domain, just scale up the plane. if you need accurate look…

as overlay of the loaded image with its own xy coordinates

edit ,i have rendered a plane with AOV and UV output.Now i have to add the math plotter.

edit,i have builded the math for the plotter

[DNorman]

I had faith that you would

[pixelgrip]

Hehe,thanks

I added the horizontal and vertical chart lines.