Getting Started with the OhioStateVolumeRenderer

Oct 22, 2008 at 10:09 PM
This set of projects and the volume renderer are targeted towards the volume renderer researcher. It offers a high degree of flexibility and programmability at the cost of easy start-up. Future efforts will work towards a end-user platform and easy start-up with your data.

To get started, download the source files using tortoiseSVN or some other system. A MS Visual Studio 2008 Pro solution file exists within the OhioStateVolumeRenderer directory. Opening this should allow you to build all of the projects. Set the OhioStateVolumeRenderer as the start-up project and run it. By default, the right has several creation tools, you can currently add volume rendered regions (ROI's), slice-planes, an triplet of axis-aligned slice planes, a sphere and a box outline or boundary. A shape or set of shapes must first be created, including a box, plane or sphere. Some Drawables require only a box or sphere, the slice-plane requires both a box (for containment) and a plane. To add any of these use the toolbar's new icon (the menu's are not really working yet). Once you have a list of drawables, you need a display surface to draw them to. This system has a concept of layers (renderable textures) that all drawables must first be rendered to. The layer control panel on the right allows you to create multiple layers and select the drawables that should be rendered to each. Note, the order the drawables are selected is the order they will be drawn (a current bug). The layers can be reordered by dragging and dropping them. By default, all of the layers are composited together in the main rendering pane.

Materials are composed of shaders, uniform variable mappings and other color and material properties. What is required is entirely dependent on the shader selected. New materials can be created in the material editor and new shaders can be created in the shaders editor. Once you have your drawables and materials, you need to assign materials to each drawable (the default is white). The is currently in the material assignments tab page on the left, but should be part of the drawable attributes. You can also change the compositing materials, reuse a layers generated texture, etc. to produce gradient or textured backgrounds, reduce the opacity of a layer, add drop shadows and many other compositing tricks. Enjoy and let us know what cool things you were able to accomplish with this tool.