3-Sweep User Manual

Last Revised: Jun 13, 2018 by Jiahui Huang

Getting Started

The following steps will guide you through a simple modeling process of a traditional Chinese Vase:

  1. Double click on 3sweep.exe to start the application. The executable is tested on a pure installation of Microsoft Windows 10 with a modern NVIDIA graphics card. The program will automatically choose software OpenGL rendering if hardware acceleration is not possible.

  2. Click 1528789230342 to bring up Select an image file window, please choose demo/bendVase.png. The system will prompt whether to use existing border file, please click Yes.

  3. By default, we are in Modeling Mode and you can perform 3-Sweep operations directly on the canvas:

    • Sweep 1: Press left mouse button and drag.
    • Sweep 2: Release mouse button and move the mouse.
    • Sweep 3: Click left mouse button and move the mouse. (Scroll middle button to change FoV if you find the perspective is not correct, middle click to change orientation)
    • If you want a bend mesh instead of a straight mesh, right click and follow the bending trajectory of the model.
  4. Your canvas now looks like this:


  5. Click img to bring up constraint window. Now select the two cylinders you have drawn previously by left clicking on them (shift click to add selection), and press 1528789998652 to add a coplanar constraint.

  6. Click 1528790078433 to start optimization.

  7. Click 1528790125031 to assign texture to select models. The system will ask you whether to remove foreground (this usually takes 8-10 seconds depending on your image size). Choose Yes to continue. Now you have successfully modeled a textured Chinese Vase. Congratulations! Click 1528790342268 to switch to Viewing Mode and use your right mouse button to rotate the camera around your model:


  8. Export obj file by first selecting two meshes and going to file Export selected meshes.


Basic Operations

In order to use 3-Sweep like a charm, you should learn and use the 4 modes in this software. They are:

  1. 1528794299250Modeling Mode : This is where the 3-Sweep magic happens, select a mesh type from toolbar: 1528793823936 and draw on the canvas.

  2. 1528794320005Manipulating Mode: You can translate, scale or rotate your model here.

  3. 1528794331023Viewing Mode: This mode is for moving the camera so that you can view the model in different angles. Click on 1528794022255 to restore camera to its original location.

  4. 1528794344789Border Edit Mode: Normally the edge of the image is detected automatically using existing algorithms. You can, however, edit the edge/border of image yourself with the four tools 1528794174698provided.

Besides, you can switch between the 4 display modes of your image:

  1. 1528794368081 Normal Picture: In this display mode the input image is displayed on the canvas.

  2. 1528794412691 Background Picture: When you run our texturing algorithm with Patch-Match, automatic foreground removal is performed. This mode shows the image without foreground.

  3. 1528794508312(-/Labeled) Border Picture: Edge map of input image, used for boundary snapping during modeling. The latter one (Labeled) assembles similar edges into groups (visualized by different colors) for better modeling performance.

You may want to switch between the appearance of your model (Shaded-Mode / Edge-Only Mode, Smooth / Flat Shading) by clicking on 1528795184000.

Grid 1528795355196 switch will display a grid in the origin of the world for visual assistance.

Importing an Image

All of our demonstrations are stored in demo/ folder. We pre-extracted some of the edges for you and the extracted edges are stored in .tsborder file within the same folder.

When you want to import an image, simply go to File Open Image (or click 1528789230342) and select your target image file. For better experience please rescale your image so that it is roughly half the size of your monitor screen.

You can change the background picture using File Open background image so that the picture displayed in Background Picture Display Mode can be replaced.

3D Modeling

Please refer to the picture below for the 3-Sweep modeling process


Selecting and Transforming

You can perform basic translating, scaling and rotating operations in Manipulating Mode. Basic mouse operations include:

Selection is enabled in Modeling Mode, Manipulating Mode and Viewing Mode. However we can not do box selection in Modeling Mode.

Copying, Pasting, Re-snapping and Deleting

When single or multiple meshes are selected, you can go to Edit Copy/Paste or simply pressing Ctrl+C and Ctrl+V to duplicate selected models.

The duplicated model, when translating to a new location, will not automatically re-snap to image boundary. Instead, you should invoke re-snapping by clicking 1528804400577 button or pressing R. Note this action will restore current camera location.

Delete a model by first select the model and then hit the Delete key.

Viewing from Different Angles

You can control your camera in Viewing Mode. Basic mouse operations include:

Assigning Texture

Textures can be applied to selected meshes by pressing 1528790125031 button or pressing T.

If you select Yes for Patch Match, the foreground in the original picture will be removed and you are brought to Background Picture Display Mode automatically.

Taking Snapshots

You can take snapshots of the current scene by pressing 1528798912493 button. This will prompts you a dialog allowing you to choose the saving directory of your snapshot.

Exporting Meshes

If you want to export the meshes for further manipulation in professional software like blender or 3D Max, first select the models and then go to file Export selected meshes to save obj file.

Material mtl file and corresponding texture images will be saved within the same folder.

Advanced Operations

Adding Constraints

There are 6 types of geometric constraints provided by this software:

  1. 1528797523550Parallelism: The main axes are parallel to each other.

  2. 1528797538555Orthogonality: The main axes are orthogonal to each other.

  3. 1528797483731Colinear Axis Endpoints: The connection of nearest endpoints and one of the axes are colinear.

  4. 1528797561117Overlapping Axis Endpoints: The nearest endpoints in image space overlap.

  5. 1528797619745Coplanar Axis Endpoints: the endpoints of axes are coplanar and the plane is orthogonal to both axes.

  6. 1528797598034Coplanar Axes: Two axes are coplanar. Note this is the only constraint that will take effects on bended meshes.

You can open the constraint window by clicking img to view all the constraints currently added. To add a new constraint, simply select the meshes and clicking on the corresponding button in constraint window. When you want to delete a constraint, simply select that constraint item and hit Delete.

When doing optimization, you may want to play with the sliding bar below controlling the balance between changing endpoints positions and changing z coordinates. See our accompanying video for demonstrations of the effects of this parameter.

Press 1528790078433 to perform final optimization. Only relevant meshes will be transformed. If the model is assigned a texture before, the texture will be recomputed.

Edit Detected Edges

Border Edit Mode 1528794344789 allows you to edit current detected edge. When you import an image, a dialog will automatically prompts up asking you what method should be used to extract the edge of image. The quality of edge map will largely influence the modeling performance so please take care of this step.

We provide two basic tools for edge extraction and one extra tool utilizing COB (Convolutional Oriented Boundaries. K.K. Maninis, J. Pont-Tuset, P. Arbeláez, and L. Van Gool. ECCV 2016) edge extraction method:

After importing, you can revoke the edge detection by clicking 1528802035322 on the toolbar of Border Edit Mode.

Snapping Pen Tool 1528802077001 can be used to draw edge map. Left click to add line segment, right click to end line segment. When right-clicked directly, the pen acts like a 'snapping pen': it will choose the nearest detected boundary from current position of the cursor. Eraser Tool 1528802295776 can be used to erase edges; please use [ and ] to control the size of the eraser.

If you want to save the border file for future demonstration, go to File Save border file. A .tsborder file will be automatically generated by our program.

Other Preferences

Go to File Settings for advanced preferences. The settings file will be stored within the same folder as the main executable file. 3-Sweep will not check the validation of the defined parameters while loading the settings file so please do not edit it directly.

The meaning of the values in settings are as follows:



If you find any problems (bug report, feature requirements, doc requirement, etc.) which is not mentioned above, please send an email to ts@heiwang.site. We will get back to you as soon as possible.