Cut shadow behind object with no full opacity

[ske_creative]

Hi Affinity Forum,

 

is there a way to cut or hide the shadow of an object, when it has a decreased opacity? When I assign an outer shadow effect to an object with a hight offset, I can see the shadow behind the object. Additionally, how would you approach the same problem when the shadow of an object bleeds into the borders of another object with low opacity? 

 

Thanks.

 

Stefan

[Dave Harris]

Have you tried setting "Fill knocks-out shadow" in the Filter Effect?

[ske_creative]

Hi Dave,

 

yeah this works for the object the effect is applied to, but not another object which overlaps the shadow. I think I have to fake the shadow with a copy of the object which I can change in its form. 

[Gear maker]

This is why I'd really like to be able to turn the fx into a layer of it's own.  When I have multiple items overlapping the drop shadow needs to be larger when showing upon the objects further away, so pieces from multiple shadows are needed.

[MEB]

@ske_creative

Regarding you second question you can add a mask to the layer that contains the first object to hide the part of the shadow that bleeds into the borders of the second (on another layer).

 

Hi @Gear maker,

I'm not sure i've understood what you mean. Can you quickly create a sample file showing the problem?

You can apply the FX to both a layer (affecting all its items at once) or single objects individually.

[Gear maker]

MEB, in the attached, the blue rectangle is twice as far behind the red as is the yellow, so I would figure that the red's shadow should spread further on the blue than it does on the yellow.  Because the light is coming down at an angle.  Likewise assuming depth of the blue rectangle the shadow of the yellow and red should be larger on the white background.

 

Sort of like I have tried to do using a mask in the right image but it didn't come off too well.  The shadow edge using a mask is roundish shape.  It needs a cleaner cutoff.  Or is there something I am missing?  (I have the intensity of the shadow way darker just to show up.)

 

I have run into this a few times and I appreciate your help if you have a way around it.

 

Test16.afdesign

[MEB]

Thanks for the file @Gear maker,

The kind of light/shadow interaction you're are describing is typical of a 3d software in a 3d environment, where the distance of the objects to the light source affect the attributes of the shadows projected by them. Affinity Designer is a 2D illustration software. There's no concept of a third dimension here and as such all objects including their shadows are treated as bidimensional entities simply stacked one above the other. It's possible to emulate certain effects, like the 3d effect you see in the FX panel through some parametric options that try to simulate some physic properties, but they are limited to the object you are applying the FX to.

 

I believe the interaction you want can be programmed, but i also think it's beyond the scope of a 2D illustration software (or at least in its grey boundaries!). The only way to create these effects is simply drawing (faking) them with the available tools, like you would do if you have to draw them on paper.

 

Soon we will be able to apply more than one FX to an object so you can simulate two shadows being projected from a single object. What we can't do is to apply a mask directly to both shadow effects independently... or even to a single one for that matter yet(?)...

[Gear maker]

I know I always try to do weird things.  My wife and granddaughter tell me that a lot.  In PS I would make each shadow then separate it into a layer of it's own where I could mask, position and resize as I wanted.  I figured that's about what ske_creative was trying to do also.

[MEB]

Doing weird things is good! Sometimes you end up discovering stuff that you wouldn't have a chance if you just had followed conventional workflows  ;)