Shadows bring PC to a halt in HF2.

DreamArchitectDreamArchitect Website User Posts: 595 Enthusiast

HI guys,

My PC though old and underpowered graphically (ATI Radeon mobility 5400 1gb) still manages to work with 3d models in an ok fashion, Not great but ok.that is until I add shadow casting. Then it goes out to 45 seconds plus a frame. Are there techniques to minimise the hit of turning on shadow casting that I should perhaps be using? I'm using point lights which I guess might not help but otherwise I'm following the compositing 3d models tutorial from @SimonKJones using a shadow catcher plane  and separate shadow light with zero intensity. I'm using HF2 for this project though will switch to HF3 from now on. I doubt that will be much faster though. So any tips greatly appreciated.

Thanks guys

Comments

  • Triem23Triem23 Moderator Moderator, Website User, Ambassador, Imerge Beta Tester, HitFilm Beta Tester Posts: 18,303 Ambassador

    If you don't need a point light, you can shift to spots and/or directional lighting, which will speed things up. Bottom line, shadow-casting point lights are the most complicated and resources-intensive. Remember, you can turn off shadows in the preview. I usually turn iff lights and shadows when animating, and don't turn them back on until grading (unless I am animating a light). 

  • DreamArchitectDreamArchitect Website User Posts: 595 Enthusiast

    Hi @Triem23

    Yeah I do turn shadows off normally too as you can imagine. It's just positioning them can be a real pain with that level of performance. Also I'm having real problems understanding how directional lights work and how to get one pointed where I want it. I am struggling to make sense of it or even to see where it's pointing. It says point towards target but where is this target? Should there be a cone in the viewer showing me what direction it's poiting in? It's really hard to work with. Do you have any tips on that too. Thanks again. Oh I'm working in HF3 now, took a copy of the project. 

    Oh and happy christmas to you and to all here. 

  • Triem23Triem23 Moderator Moderator, Website User, Ambassador, Imerge Beta Tester, HitFilm Beta Tester Posts: 18,303 Ambassador

    Think of a directional light as an infinite plane shining beams of parallel light in a particular direction. I don't remember if the target is an absolute co-ordinate (a location in the 3D space using 0,0,0 universe center as 0,0,0 target)  or a relative co-oco-ordinate (using the light position as 0,0,0), but it's one of those. 

    I agree, a cone on a light would be nice. I would also like to be able to atattach camera and light targets to a layer or point. Then the light ir camera target could be parented to an object. 

    Put a directiona. Light at 200,0,0 and set it's target to 100,0,0. Put two objects at 1000,0,0 and —1000,0,0. If the light hits the object at 1000, the target is relative to the light. If it hits the object at - 1000,  the target is absolute to universe center. 

    Make sense? 

  • DreamArchitectDreamArchitect Website User Posts: 595 Enthusiast

    I'll give this some thought then. As for the point for camera and lights. Likewise on that. It would make life much easier and more logical.

    Thanks @Triem23

  • DreamArchitectDreamArchitect Website User Posts: 595 Enthusiast

    Well I tried directional and spot lights in hf3 and the shadows worked much much better. I'm still struggling with the directional light positioning but this was about shadows and in that respect it worked well.

    Thanks for the tips @Triem23

  • AxelWilkinsonAxelWilkinson Staff Administrator, Imerge Beta Tester, HitFilm Beta Tester Posts: 5,242 Staff

    Directional lights don't have a cone, because their light doesn't behave anything like a cone. Spot lights will have a cone, and point lights will have a diameter indicating the affected area. But directional lights illuminate every object in your scene from a single direction, so there isn't any way to equate that to a cone.

  • DreamArchitectDreamArchitect Website User Posts: 595 Enthusiast

    Hi Axel

    That makes sense. I just have real trouble understanding what direction the directional light is pointing. I've yet to be able to use on correctly.

  • SimonKJonesSimonKJones Moderator Website User, HitFilm Beta Tester Posts: 4,450 Enthusiast

    To figure out the direction of a directional light, consider the position of the light and then the position of the target. The light shines from the light's position towards the target.

    However, the light rays won't converge on that point. So imagine an imaginary arrow drawn between the two positions. That's the direction of the light. But with directional lights, as Triem says, it's like having a giant panel of lights all shining in the arrow's direction.

    It creates a flatter, more even kind of light which is actually quite useful for sunlight etc.

  • DreamArchitectDreamArchitect Website User Posts: 595 Enthusiast

    Hi @SimonKJones

    I have now grasped how the type of light works from the point of view of it effectively being a panel light. 

    the problem I have is telling where the light and target are on the screen. I don't see a target anywhere. It could just be I'm doing something wrong but at the moment I am changing the target position with numbers but I really have no idea what that means in 3d space. I need to spend a bit of time just messing with directional lights to get used to it I guess. I've seen the cone on the spotlight now so that makes sense it's just these ones I struggle with. 

    thanks for the help guys

  • Triem23Triem23 Moderator Moderator, Website User, Ambassador, Imerge Beta Tester, HitFilm Beta Tester Posts: 18,303 Ambassador

    Simon, with a directional light, is target position 0,0,0 UNIVERSE 0,0,0 or using the position of the light as 0,0,0?

    This is where I re-state that it would be peachy-keen if light targets, camera targets, particle tragectory targets, and particle force/deflector positions could be parented to a point. 

  • Stargazer54Stargazer54 Moderator Moderator, Website User, Ambassador, HitFilm Beta Tester Posts: 2,726 Ambassador

    I'll second that.

  • DreamArchitectDreamArchitect Website User Posts: 595 Enthusiast

    I third it. That would make life so much easier. I'm not sure why it's not already included, especially as using points to position stuff is best practice in hitfilm for many other things.

  • SimonKJonesSimonKJones Moderator Website User, HitFilm Beta Tester Posts: 4,450 Enthusiast

    Agreed on parenting for targets generally. That would be really useful.

    A directional light's target is relative to the scene. If the target is 0,0,0 then the light will shine towards the centre point of the scene (where the world grid coordinates all meet.

  • DreamArchitectDreamArchitect Website User Posts: 595 Enthusiast

    @SimonKJones ok that helps a bit. I just need to set up a scene with one light and one model and play with it a bit until I get an understanding of how it all works.

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