mrlixm/kui

Katana OpScript for flexible instancing setup.

Liam Collod

Python Software Engineer and VFX artist. I am specialized in surfacing, lighting compositing, color-science and image-processing.

Projects

I share a lot of the code I write on my personal time so make sure to check some of those projects :

stars	name	description	tags
	lqtTextEditor	A more advanced text/code editor for PyQt
	lqtPushButtonAligned	A Qt button where you can set in which direction the text and its icon is aligned.
	AgXc	Fork of Troy.S AgX, a display rendering transform available via OCIO and more.
	Frmb	Convert file structures to right-click context menu for Windows.
	Autodesk_Maya	Collection of resources for Autodesk's Maya DCC (modelling, scene assembly, ...).
	Foundry_Mari	Collection of resources for Foundry's Mari DCC (texturing).
	Foundry_Nuke	Collection of resources for Foundry's Nuke DCC (compositing).
	Foundry_Katana	Collection of resources for Foundry's Katana DCC (scene assembly).
	lllogger	A simple lua logging module inspired from Python's one.
	opscripting	Improving Katana OpScripting workflow in a pipeline context.
	katananodling	Custom API to create and register custom Katana nodes in python.
	KUI	Katana OpScript for flexible instancing setup.
	Streamlit_Temperature2RGB	web-app to convert Kelvin temperature to RGB colorspaces.
	streamlit-colour-plotting	web-app to plot colors, images and colorspaces in graphs.

kui's Issues

Implement basic point culling using bouding boxes

Generate an instanceSkipIndex or an $hide attribute to delete points based on whether they are in the volume of a mesh's bounding box.

See https://github.com/MrLixm/KUI/blob/07c15d151d4073017d59eb5aa20e1e87c12232fe/kui/boxCulling.lua for progress.

convert TRS to matrix seems to be supported by Katana 3+

After testing the following snippet in Katana 3.6, seems the Imath module had the function used which make the PointCloudData:_convert_to_matrix() method usable in all Katana version ?

m44 = Imath.M44d()
v = {0.5,25,3}
m44:translate(Imath.V3d(v))
v = {0.5,0.5,0.5}
m44:scale(Imath.V3d(v))

print(m44:toTable())

So test KUI on Katana 3.6 and update the documentation accordingly.

Ship KUI as one single lua file.

For whoever might need this special case, offer a version of KUI in only one Lua file so it can be embedded into a Katana scene without dependencies.

Priority is very low for this one.
Comment if you need it.

Motion-blur not supported

Add support of multiple time samples for points.

It seems logical to apply this modification only on commons transformations attributes and ignore arbitrary and sources.

See RenderMan instance array example :

local numTimeSamples = pointAttr:getNumberOfTimeSamples()
local matrixArrayMap = {}

-- to get motion blur on the instances, create an instanceMatrix at each
-- time sample available from the point cloud points attribute
for idx=0, numTimeSamples-1 do
    
    local sampleTime = pointAttr:getSampleTime(idx)
    local points = pointAttr:getNearestSample(sampleTime)

    -- Each instance in array has its own matrix
    local matrixArray = {}
    local workMatrix = Imath.M44d():toTable()
    -- [...]
    matrixArray[#matrixArray+1]=workMatrix[j]
    -- [...]
    -- set the instanceMatrix for this time sample
    matrixArrayMap[sampleTime] = matrixArray

end

Fix arbitrary "additional" table when not specified.

On the instancing.data.arbitrary attribute. If the 5th column for the additional table is not specified an error is raised where something is excepting a table.
Reproduce the error again and fix it.

Improve performance for hierarchical

Since issue #5 has been addressed, testing showed that the hierarchical method is now much slower (1.61 times slower for 100k instances).

First I thought it was the inheritance of the source location attributes with self.gb:set("childAttrs", ...) which indeed seems to slow processing a lot, but computing it before didn't change anything and the previous Kui version were already using it without issue.
(see commit 3e2b490)

So something else might slow down processing.
As It's been way too much time I'm on KUI I will let this one slip and try to maybe address it in the future.

Replace tables with `Array` class instead.

Lua tables in Katana cannot store more than 2^27 (134 million) values.
Have a look at the Katana Array class to overcome this limitation.

https://learn.foundry.com/katana/5.0/dev-guide/OpsAndOpScript/Attributes/OpScript.html#Array

KUISetup node: Error on btn `common.add_row_common`

Steps:

• Create kuis node.
• Don't connect to anything
• Click on common.add_row_common button.

On node version=3

Error in line number: 86
UnbounLocalError
local variable `paramater` refrenced before assignement.