I have a placement marker (a simple plane with green corners) to visualize detected planes (via ARRaycastResult) in an ARView. This placement marker uses UnlitMaterial with a texture. Everything works fine as long as there is no other object added.
When I add another object, RealityKit also adds grounding shadow (invisible plane) right under the object. It works as a shadow plane and occludes everything behind it - including my placement marker.
Here is a picture of the placement marker (part of which is hidden under the shadow plane):
Is there any way to prevent this clipping? I was lookig for something like rendering order (as ARKit does have one), but have not fond anything in RealityKit yet.
I would like to keep the shadow plane if possible.
Edit: Added official name of the invisible plane (grounding shadow)
Reality kit automatically adds "grounding shadows" if the AnchoringComponent.Target is of type "plane". According to an Apple Engineer this can be aso simulated using a DirectionalLight with a Shadow and placing a plane (with an OcclusionMaterial) under the model. So the grounding shadow is probably also made out of OcclusionMaterial. This also explains why this grounding shadow occludes other objects.
There is an option to disable rendering of these grounding shadows. It can be done by inserting of disableGroundingShadows option into ARView's renderOptions property.
arView.renderOptions.insert(.disableGroundingShadows)
I have not yet found a way to override OcclusionMaterial (if any).
Related
In the WWDC 2017 video, apple explains about a trick to add shadows by using a directional light. Adding a directional light will cast a shadow and adding a plane will show the shadow. But I cannot seem to find mode and colour options of the cast shadow property. I am not looking to do this programatically. So is there any way there is to change the shadow type to Deferred in Xcode?
https://developer.apple.com/videos/play/wwdc2017/604/?time=2715
If I understand your problem.... Then this image explains what you are trying to do using scen view in Xcode.
You are right, adding plane and directional light with Deferred property will cast shadow. You have to set the x,y and z values of all your scene objects accordingly to show this in a proper way.
I am learning ARKit. I'm placing Virtual Objects in Augmented Reality scene and struggling in these problems!
I am using this demo project from github
1- How to add only one directional light for all (separate) nodes in SceneView of SceneKit & Move directional light with camera position? So that my added shadow can also move with light direction.
If I translate the object shadows are working as it should be. But If I rotate object now shadow should not move on the plan. They are moving because of light is at fixed position.
2- Shadow is looking fine only in case If I add only one object on the plane. But If I add two or more objects more directional lights are adding in SceneView. Now every object has more than one shadows. I want it to restrict only one shadow.
I have added light and shadow plane in sceneKit editor. (not programmatically). Here are my scenekit editor's screenshots.
3- I have read and confirmed that shadow are adding only If I set directional light property to deffered. But in this case app is crashing If I call remove all nodes from sceneView's root node. My removing nodes code is.
self.sceneView.scene.rootNode.enumerateChildNodes { (node, stop) -> Void in
node.removeFromParentNode()
print("removed ", node.name as Any)
}
You can watch my apps video for more clearance. Apps video, How it is working now
My requirement is to add only one shadow for every object. When I Rotate and translate objects shadows should look real.
I also have tried it as removing light from scn file of vase, and add a separate light.scn file having only light in it. added These two (vase and light) nodes in sceneView. But No shadow is appearing.
Directional lights are interpreted from the shader only with their direction (that one light-red vector coming out of the node in Xcode). It does not matter where the position of the light is. Directional light are often used for imitating sun light.
I implemented a similar project so here is my attempt.
I added one directional light from a separate SCN-File to the scene when I initialize the SCNScene.
My settings for it:
castsShadow: true
mode: deferred (my App is not crashing, if I remove my objects from the scene :/ )
And actually thats it to make it work in my project.
One thing about your planes: I think you have not disabled castsShadow on the planes. Therefore a user can see the planes.
Edit:
I could reproduce the crash. It does occur when removing the directional light. Thats why the app is not crashing in my project. So you could do it like me and add the directional light in viewDidLoad() for example.
Is there a way to change the appearance (size, color, etc) of the feature points in ARKit easily? (After setting debugOptions in the sceneView to ARSCNDebugOptions.showFeaturePoints I'm thinking I might have to iterate over the rawFeaturePoints and manually add custom objects into the scene at those points.
As its name suggests, ARSCNDebugOptions.showFeaturePoints is a tool to aid in debugging your app. Because the size and color of feature point indicators aren't essential to knowing where feature points are (for the sake of making sure your app is behavior correctly), Apple doesn't offer API to change their appearance. (Any more than they offer APIs for changing the colors of bounding boxes, physics shapes, and other indicators available in SceneKit debug options.)
If you want to create your own visualization for feature points, you'll need to do exactly as you suggest: read the rawFeaturePoints from the current ARFrame and use those to position content in the SceneKit scene. You might do this by creating a bunch of nodes with geometry and setting their positions. You might also look into whether it's easy to pass the entire buffer of points to create an SCNGeometry that renders in point-cloud mode.
I need to be able to interact with a representation of a cilinder that has many different parts in it. When the users taps over on of the small rectangles, I need to display a popover related to the specific piece (form).
The next image demonstrates a realistic 3d approach. But, I repeat, I need to solve the problem, the 3d is NOT required (would be really cool though). A representation that complies the functional needs will suffice.
The info about the parts to make the drawing comes from an API (size, position, etc)
I dont need it to be realistic really. The simplest aproximation would be to show a cilinder in a 2d representation, like a rectangle made out of interactable small rectangles.
So, as I mentioned, I think there are (as I see it) two opposite approaches: Realistic or Simplified
Is there a way to achieve a nice solution in the middle? What libraries, components, frameworks that I should look into?
My research has led me to SceneKit, but I still dont know if I will be able to interact with it. Interaction is a very important part as I need to display a popover when the user taps on any small rectangle over the cylinder.
Thanks
You don't need any special frameworks to achieve an interaction like this. This effect can be achieved with standard UIKit and UIView and a little trigonometry. You can actually draw exactly your example image using 2D math and drawing. My answer is not an exact formula but involves thinking about how the shapes are defined and break the problem down into manageable steps.
A cylinder can be defined by two offset circles representing the end pieces, connected at their radii. I will use an orthographic projection meaning the cylinder doesn't appear smaller as the depth extends into the background (but you could adapt to perspective if needed). You could draw this with CoreGraphics in a UIView drawRect.
A square slice represents an angle piece of the circle, offset by an amount smaller than the length of the cylinder, but in the same direction, as in the following diagram (sorry for imprecise drawing).
This square slice you are interested in is the area outlined in solid red, outside the radius of the first circle, and inside the radius of the imaginary second circle (which is just offset from the first circle by whatever length you want the slice).
To draw this area you simply need to draw a path of the outline of each arc and connect the endpoints.
To check if a touch is inside one of these square slices:
Check if the touch point is between angle a from the origin at a.
Check if the touch point is outside the radius of the inside circle.
Check if the touch point is inside the radius of the outside circle. (Note what this means if the circles are more than a radius apart.)
To find a point to display the popover you could average the end points on the slice or find the middle angle between the two edges and offset by half the distance.
Theoretically, doing this in Scene Kit with either SpriteKit or UIKit Popovers is ideal.
However Scene Kit (and Sprite Kit) seem to be in a state of flux wherein nobody from Apple is communicating with users about the raft of issues folks are currently having with both. From relatively stable and performant Sprite Kit in iOS 8.4 to a lot of lost performance in iOS 9 seems common. Scene Kit simply doesn't seem finished, and the documentation and community are both nearly non-existent as a result.
That being said... the theory is this:
Material IDs are what's used in traditional 3D apps to define areas of an object that have different materials. Somehow these Material IDs are called "elements" in SceneKit. I haven't been able to find much more about this.
It should be possible to detect the "element" that's underneath a touch on an object, and respond accordingly. You should even be able to change the state/nature of the material on that element to indicate it's the currently selected.
When wanting a smooth, well rounded cylinder as per your example, start with a cylinder that's made of only enough segments to describe/define the material IDs you need for your "rectangular" sections to be touched.
Later you can add a smoothing operation to the cylinder to make it round, and all the extra smoothing geometry in each quadrant of unique material ID should be responsive, regardless of how you add this extra detail to smooth the presentation of the cylinder.
Idea for the "Simplified" version:
if this representation is okey, you can use a UICollectionView.
Each cell can have a defined size thanks to
collectionView:layout:sizeForItemAtIndexPath:
Then each cell of the collection could be a small rectangle representing a
touchable part of the cylinder.
and using
collectionView:(UICollectionView *)collectionView
didSelectItemAtIndexPath:(NSIndexPath *)indexPath
To get the touch.
This will help you to display the popover at the right place:
CGRect rect = [collectionView layoutAttributesForItemAtIndexPath:indexPath].frame;
Finally, you can choose the appropriate popover (if the app has to work on iPhone) here:
https://www.cocoacontrols.com/search?q=popover
Not perfect, but i think this is efficient!
Yes, SceneKit.
When user perform a touch event, that mean you knew the 2D coordinate on screen, so your only decision is to popover a view or not, even a 3D model is not exist.
First, we can logically split the requirement into two pieces, determine the touching segment, showing right "color" in each segment.
I think the use of 3D model is to determine which piece of data to show in your case if I don't get you wrong. In that case, the SCNView's hit test method will do most of work for you. What you should do is to perform a hit test, take out the hit node and the hit's local 3D coordinate of this node, you can then calculate which segment is hit by this touch and do the decision.
Now how to draw the surface of the cylinder would be the only left question, right? There are various ways to do, for example simply paint each image you need and programmatically and attach it to the cylinder's material or have your image files on disk and use as material for the cylinder ...
I think the problem would be basically solved.
So I am trying to get a very basic "flashlight"-style thing going in one of my games.
The way I was getting it to work, was having a layer on top of my game screen, and this layer would draw a black rectangle with ~ 80% opacity, creating the look of darkness on top of my game scene.
ccDrawSolidRect(ccp(0,0), ccp(480,320), ccc4f(0, 0, 0, 0.8));
What I want to do is draw this rectangle EVERYWHERE on the screen, except for around a cone of vision that will represent the "light source".
What this would create would be a dark overlay on top of everything except for the light, giving it the illusion of a torch/light/flashlight.
The only way I can foresee this happening is by using ccDrawSolidPoly(), but since the position of the light source changes, so would the vertices for the poly.
Any suggestions on how to achieve this would be great.
You can use ccDrawSolidPoly() and avoid having to manually update vertices. For this you can create a new subclass of CCNode representing your light object, and do your custom shape drawing in its -(void)draw method.
The ccDraw...() functions will draw relative to the local sprite coordinates, so you can then move and rotate your new sprite to suit your needs and cocos2d will do the vertices transformations for you.
Update: I found out that you might be better off subclassing CCDrawNode instead of CCNode, as it has some facilities for raw OpenGL drawing (OpenGL's vertexArrayBuffer and vertexBufferObject internal variables and a buffer for vertices, their colors and their texCoords). If your stuff is very simple, maybe subclassing the plain CCNode is enough.
Could a png be used instead as a mask, as the layer above
Like that binocular vision you sometimes see in cartoons?
Or a filter similar to a photoshop mask that darkens as it grows outwardly to wards the edge of the screen
Just a thought anyway...
A picture of more of what your trying to explain might be good too