parameter value relative offset

[agelosc]

Hi, 

Is there a way to set a parameter value to the result of an math operation using the current value. In maya for example, in the channel editor you can set the value to "+=10" or "*=2". This will add 10 or multiple by 2 the current value. This makes sense when multiple objects are selected and you want a common relative offset and not an absolute value or an expression. 

Thanks in advance

[f1480187]

For addition/subtraction parameter ladder will work. For more complex expressions you can type in Python Shell pane:

for node in hou.selectedNodes():
    node.parm('tx').set(node.evalParm('tx') * 2)

Or type that in Python Source Editor window and press Apply. In that case you need to remove the code after execution, so it won't run again on file reload.

[agelosc]

Thank you,  I was hoping for a parameter interface feature I might have missed but thanks either way.

[f1480187]

Something like this?

You can have it by installing simple script below:

<?xml version="1.0" encoding="UTF-8"?>

<menuDocument>
    <menu>
    <subMenu id="expression_menu">
        <scriptItem id="multi_edit_values">
            <label>Multi-Edit Values</label>
            <scriptCode>
                <![CDATA[

import hou

choice, expression = hou.ui.readInput(
    'Multi-Edit Values',
    initial_contents='$SELF',
    help='Use $SELF to reference current value.',
    buttons=('Accept', 'Cancel'), close_choice=1
)

if choice != 1:
    with hou.undos.group('Multi-Edit Values'):
        for p in kwargs['parms']:
            p.setExpression(expression.replace('$SELF', p.evalAsString()))
            p.deleteAllKeyframes()

                ]]>
            </scriptCode>
        </scriptItem>
    </subMenu>
    </menu>
</menuDocument>

Save this to a file called PARMmenu.xml  (Windows example: C:\Users\user\Documents\houdini16.5\PARMmenu.xml).

If the file exist, then merge contents under nearest common tag.

[agelosc]

Well, yes exactly. Awesome, thank you.

[Richard Costin]

On 21/12/2017 at 2:12 PM, f1480187 said:

 

 

Something like this?

You can have it by installing simple script below:

<?xml version="1.0" encoding="UTF-8"?>

<menuDocument>
    <menu>
    <subMenu id="expression_menu">
        <scriptItem id="multi_edit_values">
            <label>Multi-Edit Values</label>
            <scriptCode>
                <![CDATA[

import hou

choice, expression = hou.ui.readInput(
    'Multi-Edit Values',
    initial_contents='$SELF',
    help='Use $SELF to reference current value.',
    buttons=('Accept', 'Cancel'), close_choice=1
)

if choice != 1:
    with hou.undos.group('Multi-Edit Values'):
        for p in kwargs['parms']:
            p.setExpression(expression.replace('$SELF', p.evalAsString()))
            p.deleteAllKeyframes()

                ]]>
            </scriptCode>
        </scriptItem>
    </subMenu>
    </menu>
</menuDocument>

Save this to a file called PARMmenu.xml  (Windows example: C:\Users\user\Documents\houdini16.5\PARMmenu.xml).

If the file exist, then merge contents under nearest common tag.

 

THIS.... is fantastic! Many thanks, as an ex Softie it's super helpful to be able to do this (easily) again.

Rich.