RobPerkins wrote at 2012-11-08 17:28:

I'm trying to think of a way to add something like a BillboardVisual3D such that its position stays fixed relative to the camera. Ultimately it would have an ArrowVisual3D reaching from the Billboard into the model space itself, pointing at a feature. 

This would mean that as the camera is rotated, panned, zoomed, etc, the control would stay "stuck" to the front of the frustum, as it were. 

If I understand things correctly the camera in Helix3D is the thing doing the moving during panning, rotating, and zooming; no transformations are computed on the model itself. 

How would you approach this?

objo wrote at 2012-11-12 22:15:

Yes, in this library the camera properties are modified, not the world or camera transforms.

You need to update the 3D positions of your visuals each time the camera move. I think you could create a plane at the camera 'target' position, with the camera direction as the normal vector. Then use Viewport3DHelper.GetRay and Ray3D.PlaneIntersection to calculate the 3D positions.

RobPerkins wrote at 2012-11-12 23:05:

Good; that signifies an approach I could take. What if instead of doing that, we simply position the control in the visual tree as a 2D ContentControl atop the viewport, and then extend an ArrowVisual3D from the frustum front to a world coordinate? Would the same ViewPort3DHelper and Ray3D methods be useful, or is there something simpler?

(Yes, I can figure this out on my own, but I thought the discussion here would be beneficial to others.)

objo wrote at 2012-11-13 06:05:

Yes, that should also work - I have tested 2D overlays in the ExampleBrowser/OverlayDemo. The "target" adorner and "zoom by rectangle" features in HelixViewport3D are also 2D overlays.

AQSRanck wrote at 2014-07-01 20:31:

objo wrote at 2014-07-02 13:11:

foreach (var vertex in yourPolygon)
  yourMeshBuilder.AddBox(vertex, 1, 1, 1);

AQSRanck wrote at 2014-07-02 15:35:

AQSRanck wrote at 2014-07-04 21:47:

AQSRanck wrote at 2014-07-23 15:23:

andrey7b wrote at 2012-11-20 11:16:

I'm using the components of the helixtoolkit to my application and I came across the following situation, when I create an object, a rectangle, for example, and within it I create another object, of type square, only smaller, I can't seem to find the events for this object, I want to move it using the mouse, how should I proceed? Or object created in this way does not have events?

MalcolmWadia wrote at 2012-11-28 12:57:

Hi,

Great job with this toolkit!

We are using a standard hit-test method in the Helixviewport3d but was wondering if anyone knew the best way to implement, for example, a box select method?

There doesn't seem to be any specific selector classes but it might be nice to have these.

rinaldin wrote at 2013-09-29 17:08:

PhilDotC wrote at 2014-04-17 23:12:

objo wrote at 2014-04-29 10:18:

PhilDotC wrote at 2014-04-29 13:02:

objo wrote at 2014-05-05 15:03:

_ViSoR_ wrote at 2011-11-02 00:47:

Hello,

I have model that is a composition of 17 parts. Each part uses same material with texture. This model is stored as .OBJ file and looks fine in the 3D Studio Max, but Helix renders it with incorrect positions and scallings of the textures.

Helix 2011.7 and 2010.10 produce same result.

3D Studio Max: http://i.imgur.com/lfDUf.png

Helix 3D: http://i.imgur.com/UyPOO.png

Texture: http://i.imgur.com/W2SSP.jpg

Matherial description file: http://pastie.org/2796173 

What can I do for correct rendering? Same behavior if model is saved as .3DS file. Model is about 8MB and can't be imported by Expression Blend - it crashes on import.

Thanks,

Vladimir

objo wrote at 2011-11-02 19:58:

hi Vladimir, can you also upload the .obj file?

_ViSoR_ wrote at 2011-11-02 20:11:

Hi,

It is link to the full package http://dl.dropbox.com/u/11097641/roomba_625.zip

Vladimir

objo wrote at 2011-11-03 23:11:

thanks, I see there is an error in the handling of texture coordinates here. I didn't find the bug yet, the texture coordinates (only flipped in Y direction) looks correct. Does anyone know how texture coordinates are scaled in obj files? It seems like some files have texture coordinates in ranges like [-5,5], when I expected [0,1]...

ps. MeshLab is great for testing these files!

bcblanka wrote at 2012-02-28 14:51:

Hi objo,

I think this bug is caused by the viewport unit of the image brush applied on the material. http://msdn.microsoft.com/en-us/library/system.windows.media.tilebrush.viewportunits.aspx

Here is the change I made in the code to make this OBJ model display correctly: ObjReader.cs, line 798

var textureBrush = new ImageBrush(img) { Opacity = this.Dissolved, ViewportUnits = BrushMappingMode.Absolute };

I have tested this fix on a few OBJ models and they are displayed correctly.

PS: Do you know already what is the date of the next stable release?

Cheers,

Blanka

bcblanka wrote at 2012-02-29 11:49:

I found some OBJ files where the BrushMappingMode.Absolute is breaking the texture, so this fix is not quite right. Those OBJ models have texture coordinates outside the 0-1 interval.

objo wrote at 2012-03-10 16:36:

thanks for the ViewportUnits fix - I submit it even if you have seen errors when the texture coordinates are outside [0,1]. It seems to work well on the roomba model. We should make some simple test .obj files with different variations on texture coordinates.

release plan: No, there is no release schedule since this is a side project without deadlines :) But I try to keep the default branch as stable as possible so you can always use the latest version. The Nuget package is updated at every build. The downloads are updated manually, when some bugs have been fixed or major features have been added. But I will try to make a roadmap for the project, listing some ideas of what could be added/improved...

objo wrote at 2012-03-11 20:36:

See change set f96d75e7d15a. Adding TileMode = TileMode.Tile to the ImageBrush seems to help. I also added three texture test models - they are all working now. 

Marcwell wrote at 2014-04-22 11:38:

objo wrote at 2014-04-29 10:11:

steunissen wrote at 2010-10-29 14:51:

Hi there. First of all : Great great work !! Really usefull.

But I have an issue. I used to be displaying my 3D model with the <Viewport3D>.

Now I converted to <HelixView3D>. But the "up" direction seems to be wrong... I created my model according to the "standard coordinate system" being z-axis is up.

But using HelixView3D, the up direction seems to be the Y-axis...No I am using a <RotationTransform> to display it correctly...

Please continue the good work !

Sander.

objo wrote at 2010-10-31 16:59:

hi Sander, the HelixView3D control sets the camera UpDirection to the positive z-axis. All the demo applications have z-axis up. (and the default camera position is (2,16,20), looking at the origin).

Can you add a "CoordinateSystemVisual3D" to your model, and check that the blue arrow points up? It should not be neccessary to rotate your model.

steunissen wrote at 2010-12-17 15:20:

Hi Objo,

I guess I was sleeping when I wrote my opening mail...

I'm picking up the implementation of the helix toolkit into my program. Although I am not saying your up-direction is incorrect, I was really expecting the Y-direction to be up as it is in the opengl and direct3d coordinate systems as well. (my original viewport3d has this Y=up to. So implementing your viewport is not that easy as I would have hoped....

objo wrote at 2010-12-17 15:44:

did you try setting the Camera UpDirection to (0,1,0)? I can add an example for this later. The CameraController might need a small modification for this to work properly with the "2-axis" rotation mode.

steunissen wrote at 2010-12-18 09:42:

By using the Updirection for my camera I cannot use the  HelixView3D if I am not mistaken. And I think as a consequence I loose the nice options of "showing the coordinate axes", the "view cube" etc.... I think I am going to do a axis-rotation transform on my model... Not that nice, but hopefully effective...

objo wrote at 2010-12-19 12:34:

see the new UpDirectionDemo :-)

steunissen wrote at 2010-12-21 08:54:

Thanks ! Downloading it now....

michaeldjackson wrote at 2012-10-18 14:58:

Does anyone know how to add "X", "Y", "Z" text on the coordinate system, without modifying source code?

RobPerkins wrote at 2012-10-19 17:43:

To do this without modifying the source code of Helix3D, you would have to reconstitute the <style> of the HelixViewport3D. You can find the original style in the Generic.xaml file in the codebase for a template.

Copy and place it in any resource dictionary, and then modify the "PART_CoordinateView" portion to read:

                            <Viewport3D x:Name="PART_CoordinateView" 
                                        Width="{TemplateBinding CoordinateSystemWidth}" Height="{TemplateBinding CoordinateSystemHeight}" Margin="0" 
                                        HorizontalAlignment="{TemplateBinding CoordinateSystemHorizontalPosition}" VerticalAlignment="{TemplateBinding CoordinateSystemVerticalPosition}" 
                                        ClipToBounds="False" Visibility="{TemplateBinding ShowCoordinateSystem, Converter={StaticResource BoolToVisibilityConverter}}">
                                <local:ArrowVisual3D Point2="8 0 0" Fill="#964B4B" />
                                <local:TextBillboardVisual3D  Position="9 -2 1" Text="X" Height="10" />
                                <local:ArrowVisual3D Point2="0 8 0" Fill="#4B964B" />
                                <local:TextBillboardVisual3D Position="-2 9 1" Text="Y" Height="10" />
                                <local:ArrowVisual3D Point2="0 0 8" Fill="#4B4B96" />
                                <local:TextBillboardVisual3D Position="-2 -1 9" Text="Z" Height="10" />
                            </Viewport3D>

michaeldjackson wrote at 2012-10-19 17:56:

                            <Viewport3D x:Name="PART_CoordinateView" 
                                        Width="{TemplateBinding CoordinateSystemWidth}" Height="{TemplateBinding CoordinateSystemHeight}" Margin="0" 
                                        HorizontalAlignment="{TemplateBinding CoordinateSystemHorizontalPosition}" VerticalAlignment="{TemplateBinding CoordinateSystemVerticalPosition}" 
                                        ClipToBounds="False" Visibility="{TemplateBinding ShowCoordinateSystem, Converter={StaticResource BoolToVisibilityConverter}}">
                                <local:ArrowVisual3D Point2="8 0 0" Fill="#964B4B" />
                                <local:TextBillboardVisual3D  Position="9 -2 1" Text="X" Height="10" />
                                <local:ArrowVisual3D Point2="0 8 0" Fill="#4B964B" />
                                <local:TextBillboardVisual3D Position="-2 9 1" Text="Y" Height="10" />
                                <local:ArrowVisual3D Point2="0 0 8" Fill="#4B4B96" />
                                <local:TextBillboardVisual3D Position="-2 -1 9" Text="Z" Height="10" />
                            </Viewport3D>

RobPerkins wrote at 2012-10-19 18:00:

I can't see your code, but, you need the entire style from the Default.xml for HelixViewport3D; I only posted the part that needs changing.

The PART_CoordinateView x:Name must stay attached to this Viewport3D snippet within the style.

michaeldjackson wrote at 2012-10-19 19:09:

RobPerkins wrote at 2012-10-19 21:50:

Two PipeVisual3D's and a sphere, scaled to the sizes you need, should resemble a pipe elbow. You'd need to write the class that emits it and scale the results.

I'm working on similar graphics problems but I don't have employer permission to release code.

You could also use texture coordinates, correlated with triangle vertices, and combined with a GradientBrush to plot color data along your surface. A pipe geometry is a relatively simple thing to tessellate. It wouldn't be hard to further tessellate so that you get vertices at points along the pipe that align with your data results.

objo wrote at 2012-10-22 22:46:

I added the coordinate system labels to the default template. I hope it is ok for everyone...

Thanks for sharing the code, Rob!