Python script - how to change and apply material base color

Development Pipeline & Plugins Editor Scripting
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1

Hi,

How would one go about changing the base color for a material by scripting (I’ve got >5k that needs altering and I really want to avoid manual work)?

Here’s what I’ve tried

m = unreal.EditorAssetLibrary.load_asset('/Game/Materials/some_material_1')
mi = unreal.MaterialInstanceConstant(m)
print(unreal.MaterialEditingLibrary.get_material_instance_vector_parameter_value(mi, 'Param'))
# <Struct 'LinearColor' (0x7fd05b30b5b0) {r: 0.000000, g: 0.000000, b: 0.000000, a: 1.000000}>
unreal.MaterialEditingLibrary.set_material_instance_vector_parameter_value(mi, 'Param', unreal.LinearColor(r=0.23, g=0.12, b=0.18, a=0.33))
print(unreal.MaterialEditingLibrary.get_material_instance_vector_parameter_value(mi, 'Param'))
#<Struct 'LinearColor' (0x7fd05691e150) {r: 0.230000, g: 0.120000, b: 0.180000, a: 0.330000}>
unreal.MaterialEditingLibrary.update_material_instance(mi)

All seems good, but - nothing changes?

In the editor there’s an option to Apply changes? Is that the missing part here? How can I reach that by script?

Appreciate your help on this!

Thanks,
Sture

2

seems to work fine.

mi = unreal.EditorAssetLibrary.load_asset('/Game/Tests/Materials/MI_someMat.MI_someMat')
unreal.MaterialEditingLibrary.set_material_instance_vector_parameter_value(mi, 'Color', unreal.LinearColor(r=0.5, g=0.0, b=0.0, a=1.0))
unreal.MaterialEditingLibrary.update_material_instance(mi)
unreal.EditorAssetLibrary.save_loaded_asset(mi)