Performances problem with shadows and texture offset

Scripting Issues
#1

Hello, I’ve a performance problem. I’ve this simple application: a quad with a texture on it, and the offset of the texture changes. This is the code:

from panda3d.core import TextureStage
from pandac.PandaModules import Spotlight

from panda3d.core import loadPrcFileData
loadPrcFileData( '', 'want-pstats 1' )
loadPrcFileData( '', 'show-frame-rate-meter #t' )

import direct.directbase.DirectStart

base.disableMouse()
camera.setPos( 0, -2.5, 2.5 )
camera.setHpr( 0, -48, 0)

model = loader.loadModel( 'quad' )
model.reparentTo( render )

ts = TextureStage('ts')
model.setTexture( ts, loader.loadTexture('img2.jpg') )

offset = 0
def update( task ):
  global offset
  offset += .001
  model.setTexOffset( ts, offset, offset )
  return task.cont
taskMgr.add( update, 'TextureUpdate' )

def setupLight():  
  light = render.attachNewNode( Spotlight( 'Spot' ) )
  light.setPos( ( 20, 20, 20 ) )
  light.lookAt( 0,0,0 )
  light.node().setShadowCaster( True, 1024, 1024 )
  render.setLight( light )

render.setShaderAuto()
  # it costs 2 ms without the texture movement and 8 ms with that

setupLight()
  # it costs 2 ms without the texture movement and 30 ms with that

run()

I would like to see these two effects: shadows and texture offset. Both cost few milliseconds if used separately, but, if I use them together then the performances drop (and I can’t use them in real contexts :frowning: ).

For example, with render.setShaderAuto() and lighting each frame costs 28 ms more.

Here’s the complete code with resources.

Is my lighting setup wrong? Thank you!

#2

The problem is that the setTexOffset() call changes the render state every frame, which when applied to a node that also has setShaderAuto() in effect, means that the auto-shader has to be recomputed every frame.

Solution: don’t apply setShaderAuto() to the same node that receives the setTexOffset() call. For instance, specify:

model.setShaderOff()

David

#3

Thank you David! Now performances are OK. This solution implies that the quad doesn’t receive shadows, is it right? Is there a way to get shadows and variable texture offset?

#4

You’ll have to apply a custom shader to the quad to avoid the problem of the auto-shader.

David

#5

Ok, thanks!