Slow rendering in v3.5.5 vs v3.36 (calling AddNoiseEffect from codelab)

[Tanel]

Can you spot why is this code several times slower in v3.5.5 (and 3.5.4) than v3.36? Is there some version specific optimizations I should implement?

I measured speed difference 3...5 times on different size images (My system is XP SP3, Core2Duo, 3.5 GB).

Below effect is actually stripped down to just call AddNoiseEffect and render the result.

In v3.36 it renders fast.

In v.3.5.5 (and 3.5.4) it is slow.

Codelab designed effect:

#region UICode
int Amount1 = 50; // [0,100] Amount
#endregion

unsafe void Render(Surface dst, Surface src, Rectangle rect)
{
   // Setup for calling the Noise function
   AddNoiseEffect noiseEffect = new AddNoiseEffect();
   PropertyCollection nProps = noiseEffect.CreatePropertyCollection();
   PropertyBasedEffectConfigToken nParameters = new PropertyBasedEffectConfigToken(nProps);
   nParameters.SetPropertyValue(AddNoiseEffect.PropertyNames.Intensity, 40);
   nParameters.SetPropertyValue(AddNoiseEffect.PropertyNames.Saturation, 0);
   nParameters.SetPropertyValue(AddNoiseEffect.PropertyNames.Coverage, 100.0);    
   noiseEffect.SetRenderInfo(nParameters, new RenderArgs(dst), new RenderArgs(src));
   // Call the Noise function
   noiseEffect.Render(new Rectangle[1] {rect},0,1);

   // Now in the main render loop, the dst canvas has a noisy version of the src canvas
   for (int y = rect.Top; y < rect.Bottom; y++)
   {
       ColorBgra* srcPtr = src.GetPointAddressUnchecked(rect.Left, y);
       ColorBgra* dstPtr = dst.GetPointAddressUnchecked(rect.Left, y);
       for (int x = rect.Left; x < rect.Right; x++)
       {
           ColorBgra DstPixel = *dstPtr;
           ColorBgra SourcePixel = *srcPtr;

           // will render some more stuff here

           *dstPtr = DstPixel;


           srcPtr++;
           dstPtr++;
       }
   }
}

[pyrochild]

It's not very slow here, but this is even faster:

#region UICode
int Amount1 = 50; // [0,100] Amount
#endregion

AddNoiseEffect noiseEffect;

unsafe void Render(Surface dst, Surface src, Rectangle rect)
{
   // Setup for calling the Noise function
   if (noiseEffect == null)
   {
       noiseEffect = new AddNoiseEffect();
       PropertyCollection nProps = noiseEffect.CreatePropertyCollection();
       PropertyBasedEffectConfigToken nParameters = new PropertyBasedEffectConfigToken(nProps);
       nParameters.SetPropertyValue(AddNoiseEffect.PropertyNames.Intensity, 40);
       nParameters.SetPropertyValue(AddNoiseEffect.PropertyNames.Saturation, 0);
       nParameters.SetPropertyValue(AddNoiseEffect.PropertyNames.Coverage, 100.0);    
       noiseEffect.SetRenderInfo(nParameters, new RenderArgs(dst), new RenderArgs(src));
   }
   // Call the Noise function
   noiseEffect.Render(new Rectangle[1] {rect},0,1);

   // Now in the main render loop, the dst canvas has a noisy version of the src canvas
   for (int y = rect.Top; y < rect.Bottom; y++)
   {
       ColorBgra* srcPtr = src.GetPointAddressUnchecked(rect.Left, y);
       ColorBgra* dstPtr = dst.GetPointAddressUnchecked(rect.Left, y);
       for (int x = rect.Left; x < rect.Right; x++)
       {
           ColorBgra DstPixel = *dstPtr;
           ColorBgra SourcePixel = *srcPtr;

           // will render some more stuff here

           *dstPtr = DstPixel;


           srcPtr++;
           dstPtr++;
       }
   }
}

[Rick Brewster]

If you're doing a null-checked, deferred instantiation there, don't forget to reset this.noiseEffect to null in OnSetRenderInfo (call its Dispose method first, too).

[pyrochild]

I don't think we can get to OnSetRenderInfo from CodeLab anymore

[BoltBait]

"Anymore?" You never could.

I've been brainstorming how to give access, but I haven't come up with a good way yet.

[Tanel]

pyrochild,

thank you so much for the example.

I can confirm that this is equally fast in v3.5.5 and v3.36. The speed is now the same as my original code in v3.36.

I couldn't follow Rick's advice, but there is no obvious problem either.