4.9. Tutorial: The Web Optimizer tool

Starting Point

Load a project with a finished textured 3D model you wish to publish on the web. If you wish to use view-dependent textures (3DSOM Java Viewer format only) you will need to rebuild these (see View-dependent textures.)

Step 1

Hit the Export model... button. The selected file type should be "3DSOM Java Viewer" or "3DSOM Flash Viewer". If this is not the case, select this type from the drop down menu.

Step 2

Launch the optimizer by selecting the Run Optimizer... button. You will be presented with one of the following dialogs.

The optimizer allows you to switch between the Java and Flash output formats using the drop-down menu. The format specific settings are shown below the drop down menu.

The 3D model data is divided into two parts - the geometry and the texture. You can control the output quality of each independently.

Step 3

The top line relates to the geometry quality. You can vary the desired quality from 0 (lowest quality) to 100 (highest quality). Either edit the number directly or click the arrow buttons to the right of the input field.

On the right hand side you will see the size of the geometry data at the selected quality settings and the equivalent download time in seconds at the currently selected connection speed.

To see the effect on download time for different connection speeds simply select the desired connection speed from the drop-down menu. This is the web connection speed of a target user surfing the web. In general dial-up users would have connection speeds of between 28Kbps and 56Kbps whereas a broadband user may have connections of between 128Kbps and 512Kbps.

Step 4

Try varying the geometry quality so that a user with a 56Kbps connection can download all the geometry data in around 5 seconds.

Click the Preview button to see the model at the current settings. 3DSOM Pro will save the model in a temporary file and launch a separate application window to view the model. You should be able to see the web optimizer window and the 3D viewer application window side by side.

Step 5

The second line relates to the texture quality. You can edit this as before. For the Java version, the texture data is split across a number of separate files or "chunks" (known as progressive textures or streaming). The chunks are downloaded in order to gradually improve the quality of the textures on the model. As soon as the first chunk is downloaded a low resolution model will be displayed.

The flash format uses as single progressive JPEG texture map which will be streamed and cached by the web browser. The low resolution model will be shown after the first "chunk" of image data has been downloaded.

On the right hand side of the texture quality field you will see the total texture data file size and equivalent download time at the currently selected connection speed. Also in brackets you will see the file size and download time for the first chunk of data.

Try varying the texture quality settings so that a user with a 56Kbps connection can download the first chunk of texture data in under 2 seconds whilst a user with a fast 512Kbps connection can download all the texture data in under 5 seconds.

You will need to hit the Preview button every time you wish to view the model with the new settings.

Step 6

You can change the width and height of the viewer applet or movie by entering the desired values in the "viewer_width" and "viewer_height" fields. The remaining format specific settings are described below.

Flash viewer options The 3DSOM Flash Viewer is a software renderer based on Flash AS3 scripting. For interactive rendering speed this software renderer can only handle a limited number of triangles. A mechanism is provided so that a decimated "interactive quality" model is displayed when the model is being rotated. Once the model is stationary the full quality model is then displayed. To use this novel feature, make sure the checkbox labelled "Export multiscale for fast interaction " is selected. You can then specify the number of triangles in the high quality mesh (displayed when static) and the number of triangles in the interactive quality mesh (displayed when rotating the model). TIP: We recommend using up to 6000 triangles in the interactive quality mesh and up to 12000 triangles in the full resolution mesh for the Flash 3D format.

Step 7

When you are happy hit the OK button and the model viewer application will automatically be closed.

Enter the desired filename and directory and hit the Save button to export the final model.