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Just a big "Thank You"

Anonymous 9 years ago updated by ไอยดา สุรีวงค์ 2 years ago 1
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Jac312 wrote at 2010-06-06 18:57:

You have done a wonderful and useful job. I'm using your library in a 3D Xbap application that will help design precasted concrete products once finished. The toolkit works like a charm. So: a big "Thank You" and keep going. Jacques PS: ZoomToFit() works perfectly

objo wrote at 2010-06-07 07:44:

thanks for the feedback! good to hear that the zoomtofit function works for you!


Progress - keep it going please

Anonymous 9 years ago updated by anonymous 4 years ago 1
This discussion was imported from CodePlex

stfx wrote at 2010-02-02 18:50:

Hey I just registered here to tell you how awesome that toolkit is. I use a modified version of it and it works perfectly. Do you have any progress on the code so far like object transformation (position, rotation, size) or maybe fit screen to object and fit to show all objects?

Please dont give up on it I really appreciate it.

Oh yeah you should consider to rename it to Helix Engine - sounds so much cooler :D

PS: I can send you the modifications if you are interested.

objo wrote at 2010-02-21 18:13:

Thanks for your feedback!! Sure, this project just started - I hope to get more work done on it soon. I have added you as a developer, you are welcome to submit improvements! There is a simple manipulator class for object transformation (translation only) in the toolkit now, but I am sure this needs more work. Do you have solutions to this? And the "fit screen to object" feature? That's a feature I would really like to have included!

Engine or toolkit - I like "toolkit" since this is mostly a collection of tools and helper classes - not replacing or encapsulating the wpf 3d engine. 


TextBillboardVisual3D with Mouse-Events?

Anonymous 9 years ago 0
This discussion was imported from CodePlex

31337 wrote at 2012-11-27 12:28:

Hallo, is it possible to add the TextBillboardVisual3D as ModelUIElement3D?

31337 wrote at 2012-11-30 12:22:

Figured it out myself.

"ContainerUIElement3D" is the answer.

bennasi wrote at 2012-12-03 10:47:

Could you please elaborate on this a bit more? A code example would be nice. Thanks


CAD formats

Anonymous 9 years ago 0
This discussion was imported from CodePlex

vindex wrote at 2011-12-17 11:55:


First of all, great job, and thank you again. I'm a grateful user of Oxyplot, and here i find you again!


And now my question... have you any plans to give support to some CAD formats like .step, .sat,  or .iges?

objo wrote at 2011-12-19 09:24:

Sorry, no plans to implement readers for step, sat or iges. Only simple formats using triangular/quadrilateral meshes.

I might add import for a subset of the DXF format (polylines/curves and simple surfaces).

openNURBS is also interesting, would like to add a demo using the .net library:


Loaded objects flip upside down when zooming

Anonymous 9 years ago 0
This discussion was imported from CodePlex

Elementu wrote at 2012-02-22 15:53:



I have several helix controls in my application. Some of them are froze to give the feeling of a 2D display than cannot be rotated.

The one that is not froze uses a perspective camera and the other 2D use Orthographic Camera.

The problem that I'm facing is that when I zoom into the 2D controls my objects flip upside down. this can be seen also on the view cube the view changes, however even if I bring the view(guiding myself after the view cube) as it was before the objects are still upside down.

However if I reset the camera the objects will be in the correct position.

Is there a way to prevent this behavior and stop it from happening?


Thank you in advance.

elementu wrote at 2012-02-23 11:07:


What I discovered in my investigation is that in the CameraContoller.cs(HelixToolkit.Wpf.CameraController) in the OnTimeStep method at the point were the this.ZoomHandler.Zoom method is called, when the "this.zoomSpeed * time" parameter has a large value this bug will occur. In fact this bug occurred especially if I ran my application a slower machine. If I ran it on my main machine the bug only occurred if I added a thread.sleep of 500 or 1000 before calling the Zoom method.

So from the Zoom method the delta parameter is passed further in the ChangeCameraWidth method because my camera is an OrthographicCamera one.

Finally in the ChangeCameraWidth method to prevent the delta parameter from having a value that is too large  if the absolute value of the parameter is larger that 1 ( Math.Abs(delta) >= 1 ) then delta will take the value "delta = delta % 1" .

Having done this even if I add the delay or run the application on a slower machine the bug is not reproduced anymore.

I noticed that in the ChangeCameraPosition method that is called from the Zoom method in case my camera is a PerspectiveCamera not an OrthographicCamera there is a section of code with similar functionality to limit the value of the delta parameter.

if (delta < -0.5)
      delta = -0.5;

On a first look the behavior seems the same as before and everything looks all right with the change, except the bug that does not occur anymore.

What I want to ask you is what could be the implications of the change(the limitation of the delta value) I made, what is the case or were could it have a negative effect on the behavior or performance of the HelixToolkit ?


Thank you.

objo wrote at 2012-03-10 15:41:

thanks for debugging this! I added the clamping on the delta value as you suggested (change set c213bd42d8f7), and this seems to correct the problem. It limits the maximum zoom-out speed, but 50% zoom out per zoom event should be sufficient, I think.

stfx wrote at 2012-05-21 00:05:

Nice fix - btw this also occured on a perspective camera but yea fixed after that commit.

Another problem related to zooming is that if you zoom in too far (as far as you can) the camera will start to wobble at the end).

Fixed it by modifying the CameraHelfer.LookAt function like this:


        public static void LookAt(
            PerspectiveCamera camera, Point3D target, Vector3D newLookDirection, double animationTime)
            Point3D newPosition = target - newLookDirection;

            // prevent zooming in until camera gets wobbly due to precision loss
            if (Math.Abs(newPosition.Z) > 0.01)
                AnimateTo(camera, newPosition, newLookDirection, camera.UpDirection, animationTime);
EDIT: This fix is definately not correct

How to retrieve info colors / brush from material class

Miller 8 years ago 0


i've some trouble in getting color information ModelUIElement3D.

The question is understand which is the proper color when the user select something in the drawing.

From ModelUIElement3D you can retrieve GEOMETRYMODEL3D and MATERIAL.

But i'm stuck because the Visualstudio doesn't allow me to compare:

" If model.Material = Materials.Blue Then

End If"

The error is : "=" equal isn't allowed for material class.

I've tryied also to set a name to material: "model.Material.SetName("Blue")"

It give me an error saying that name material property is readonly.

Any other advice???




Problem with material when adding new child to the group

Anonymous 9 years ago 0
This discussion was imported from CodePlex

Tapir wrote at 2012-11-08 08:13:

I have a problem with adding new child to group. Regardless of which material i use, all figures are filled with color of the last added one. Any idea how to solve this problem?

        static private Model3DGroup DrawLayers(int noOfLayers)
            Material materialFiber = new DiffuseMaterial(new SolidColorBrush(Colors.Lime));
            Material materialCopper = new DiffuseMaterial(new SolidColorBrush(Colors.Orange));
            HelixToolkit.Wpf.MeshBuilder builder = new HelixToolkit.Wpf.MeshBuilder();
            Model3DGroup group = new Model3DGroup();

            for (int i = 0; i < noOfLayers; i++)
                if (i == 0)
                    builder.AddBox(new Point3D(0, 0, 0), 15, 15, 1);
                    builder.AddBox(new Point3D(0, 0, 2*i), 15, 15, 1);

                MeshGeometry3D layer = builder.ToMesh();

                if (i % 2 == 0)
                    GeometryModel3D model = new GeometryModel3D() { Geometry = layer, Material = materialFiber, BackMaterial = materialFiber };
                    GeometryModel3D model = new GeometryModel3D() { Geometry = layer, Material = materialCopper, BackMaterial = materialCopper };
            return group;

objo wrote at 2012-11-08 08:25:


var builder = new HelixToolkit.Wpf.MeshBuilder();

inside your loop?

otherwise you are appending more and more boxes to your geometry...

Tapir wrote at 2012-11-08 08:31:

Works perfectly. Thanks a lot!


SharpDX - Transparency from image

Anonymous 9 years ago updated by kanpat88 1 week ago 335
This discussion was imported from CodePlex

geoarsal wrote at 2014-03-07 10:05:


how can i enable transparency from image for textures ??

In WPF3D, all i need to do is to create the diffuse material with image brush and use it. In SharpDX fork, I had created PhongMaterial and set its DiffuseMap to the same image i used in WPF3D, but here the transparent region are rendered as Black.


Rogad wrote at 2014-03-08 16:05:

I used PNG textures. Also read this about how you need to order transparent parts :

I still have problems with layered transparency though, when one part of the model overlaps the other it does not look right.

geoarsal wrote at 2014-03-08 17:48:

Thank you Rogad for your reply.

I would like to know have you used PNG textures to attained transparency in "SharpDX fork of Helix Toolkit" ?? because the link you have provided is about transparency in WPF3D but I need transparency in SharpDX.

P.S. I already got the transparency using image texture in WPF3D but I require same functionality in SharpDX fork using that same image.

Rogad wrote at 2014-03-08 17:56:

Sorry I did not realise you were asking about SharpDX. I have not tried it, because I couldn't see how to get support, so gave up on it.

geoarsal wrote at 2014-03-12 19:04:

After debugging the code, I had resolved this issue. Following are the changes I needed to make in Helix SharpDx.

In the pixel shader "PShaderPhong" method, alpha value is taken explicitly from the diffuse material.

Current Code "Default.fx"
/// set diffuse alpha
I.a = vMaterialDiffuse.a;
Fix "Default.fx"
I.a = vMaterialDiffuse.a * vMaterialTexture[3];
Also the conversion of texture map is done through BMP encoder, however apparantly it looks like BMP encoder doesn't support alpha in texture map. Changing bmp encoder to png encoder will resolve this issue.

Current Code "RenderUtil.cs"
public static byte[] ToByteArray(this System.Windows.Media.Imaging.BitmapSource bitmapSource)
            using (MemoryStream ms = new MemoryStream())
                var encoder = new System.Windows.Media.Imaging.BmpBitmapEncoder();
                return ms.ToArray();
Fix "RenderUtil.cs"
public static byte[] ToByteArray(this System.Windows.Media.Imaging.BitmapSource bitmapSource)
            using (MemoryStream ms = new MemoryStream())
                var encoder = new System.Windows.Media.Imaging.PngBitmapEncoder();
                return ms.ToArray();

objo wrote at 2014-04-29 10:57:

I have forwarded this to the guys working on the sharpdx fork.

Rogad wrote at 2014-05-24 18:16:

Is there a similar fix for Helix ?

For my project this is the main area where Helix does not seem to work right.

Despite following various tutorials/guides on transparency, such as putting the transparent textures last I still end up with this :

Some of the transparency is working, but as you can see not all.

Would really like to fix this :)

Rogad wrote at 2014-05-30 16:46:

Anyone ? Objo ? Are you still with us ? :)

objo wrote at 2014-05-30 22:56:

hi Rogad, yes I am following the discussion, but don´t know how to solve this. How are you rendering the hair? Are you using SharpDX or WPF? Can you create a demo application we can include with the library?

Rogad wrote at 2014-05-30 23:08:

Hi :)

I'm using WPF and Helix. I have not used SharpDX for anything yet, I was trying to find some documentation for it or support, but haven't found much yet.

Unfortunately I cannot turn this into something distributable. The models I had to buy from Daz3D and I cannot redistribute them like that.
Under review

Need Advice On How To Sync Coordinate Systems

Anonymous 9 years ago updated by ไอยดา สุรีวงค์ 2 years ago 2
This discussion was imported from CodePlex

BogusException wrote at 2014-07-06 20:41:


I'm still getting using the FlightsDemo to create a proof for a project I want to do. The objective is a rotating globe with the flights on them, just like they are in the demo files included with the product today.

I am running into an issue/situation whereby I can't figure out how to translate the mouse click to the proper coordinates on the Sphere... The biggest demonstration of this issue is this:

-As the Sphere is rotating:
            <EventTrigger RoutedEvent="Canvas.Loaded">
                        <DoubleAnimation x:Name="Rotate360"  From="0" To="360" Duration="0:2:00" AutoReverse="False" 
                                         RepeatBehavior="Forever" Storyboard.TargetName="rotation" 
                                         Storyboard.TargetProperty="Angle" />
<t:SphereVisual3D x:Name="TheEarthSphere" 
                              Material="{StaticResource EarthJPG}"
                              PhiDiv="25" >
                                <AxisAngleRotation3D Axis="0,0,1" Angle="0" x:Name="rotation" />
...the lat & lon at the top left of the WPF Window do NOT update. They are tied to the non-animating coordinate system of the Viewport, which is illustrated by the little cube on the bottom right:

-As the cube is rotating, when I do click on it, based on the current coordinates of the Viewport (little cube, lat & lon at top left of display), that is where the tube will be placed. This means:

-No matter what the rotating sphere is doing, the lines will be placed on the sphere at THOSE coordinates, NOT where he mouse was over when clicked.
-Imagine you are clicking on a rotating sphere in the same (relative) position, say, dead center. The tube (flight) is placed on the rotating sphere, but always in the same place.

I know this is just a matter of finding a way in Helix 3D to rotate the little cube at the bottom right as the sphere is rotating, but there are virtually no docs, and I can't figure out how to tie them together.

Q: In other words, how to make the little navigation cube at the bottom right reflect the position of the sphere as it rotates? Or can I just get the Sphere coordinates from a click somehow?

An example might help.

Here is the window as it starts. Note the nav cube (we'll call it) position at bottom right, and where the sphere (earth) is in it's rotation, as well as the lat & lon at the top left:

You should notice a few things from the above 2 screenshots:
  1. The position of the mouse is (almost) the same, and so is the lat & lon at top left.
  2. The sphere, however, has rotated between these 2 images, and the mouse is obviously over a different lat & lon on the 2nd shot as it was in the 1st.
  3. The nav cube at bottom right stays still.

It appears that the nav cube is for the viewport coordinate system by default (would love to change that to the Sphere).
The Shpere, and it's child material) are rotating fine.
The click/hit point(s), though do NOT reflect the 3D point on the sphere clicked, but rather the 3D point in the viewport coordinate system.
I have even tried to rotate the camera around the Sphere, but I can't find documentation on how to accomplish this (leave Sphere static, rotate the camera in an orbit around sphere, looking at 0,0,0)...

My Request:

Please tell me how to tie the place the mouse is clicked on the sphere with the sphere coordinates of that click/hit.

Any hints, guidance, example greatly appreciated!

P.S. Is there an example of AnimateOpacity?

objo wrote at 2014-07-11 21:55:

Can anyone help on this? Is there a bug? Transform of the model/visual not being included?

BogusException wrote at 2014-09-18 19:00:

Still no thoughts on the question above:

P.S. Is there an example of AnimateOpacity?

SphereVisual3D+ImageBrush incompatible with cutting planes?

Anonymous 9 years ago updated by ไอยดา สุรีวงค์ 2 years ago 2
This discussion was imported from CodePlex

joaoportela wrote at 2012-03-13 20:55:

I was making half a sphere by cutting a SphereVisual3D with a cutting plane, but this made my (textured) sphere disappear. The sphere renders normally without cutting planes

So that I am clear:

This works:

MyVisual = new SphereVisual3D() { ThetaDiv = 60, PhiDiv = 30 };
var textureBrush = new ImageBrush(new BitmapImage(TEXTURE_URI));
MyVisual.Fill = textureBrush;

This doesn't:


MyVisual = new SphereVisual3D() { ThetaDiv = 60, PhiDiv = 30 };
var textureBrush = new ImageBrush(new BitmapImage(TEXTURE_URI));
MyVisual.Fill = textureBrush;
HelixToolkit.Wpf.CuttingPlaneGroup cutPlane = new CuttingPlaneGroup();
cutPlane.CuttingPlanes.Add(new Plane3D(new Point3D(0, 0, 0), new Vector3D(0, 0, -1)));

If I use a SolidColorBrush it works fine with or without cutting planes.
Am I doing something wrong or is this a know issue?



objo wrote at 2012-03-14 00:33:

this is probably a limitation with the current implementation. I have not tested it with texturecoordinates and imagebrush materials.

joaoportela wrote at 2012-03-21 12:06:

Thanks for the information. I ended up manually building an half sphere for this.