HOW TO USE AMBIENT OCCLUSION
Ambient occlusion is a technique which consists in approximating global illumination. It enhances depth perception in the picture you are watching and gives it a more natural character. Using ambient occlusion in Flow Architect Studio 3D is very easy and you can use it in every project in an easy way.
The ambient occlusion technique in Flow Architect Studio 3D makes use of lightmaps. A lightmap is a texture used for storing surface lighting information for an object or a wall. Ambient occlusion information for surfaces is stored in lightmaps.
In order to use ambient occlusion, check the Lightmaps enabled property in a map’s parameters, save the map and compile it. Then choose the Render ambient occlusion option from the Toolsmenu.
Rendering ambient occlusion is a time consuming process that consumes all the computer processing power. After rendering is finished, the ambient occlusion data is saved to the file that is loaded when the visualization is started. If some changes are made to the map, it is most probable that light the map data file will not longer fit the map. In this case, it will not be loaded and it needs to be rendered again.
In Flow Architect Studio 3D, there are a few parameters that control ambient occlusion accuracy, quality and appearance. In order to change those parameters, click on the map on the navigator tab on the left side of the program or unselect all objects then choose the Properties tab in the panel on the right side. The following parameters control ambient occlusion:
|
LM default brush grid |
Sets default lightmap accuracy in the map’s units (cm) for Blocks and Surfaces. The lesser the value, the more detailed the lightmaps are, but it takes longer to render ambinet occlusion and the lightmap file becomes larger. For example, changing this value from 8cm to 4cm causes rendering to take four times longer and makes the lightmap file about four times larger. The default value is 8cm. |
|
LM default model grid |
The same as above but is refers to models. The default value is 8cm. |
|
AO Rays |
Sets the amount of rays cast for a single sample. The more rays are cast the more accurate ambient occlusion is calculated. Too few rays result in visible noise. The default value is 500. |
|
AO Distance |
Sets the distance for ambient occlusion calculations. Increasing this value will make the ambient occlusion effect stronger. The default value is 100cm. |
|
AO Samples |
Sets the number of ambient occlusion samples for one lightmap point. Higher values make rendering take more time but allow you to get rid of the edge aliasing problem (the stairs effect) when values change sharply on a lightmap surface. The default value is 4. |
Lightmap accuracy can also by controlled per object. In order to do this, select an object and choose the LM gridproperty on the Propertiestab. The value equal to 1.0 means that the object has the default lightmap grid. 0.5 means that the lightmap grid for the object is two times smaller that the default so its lightmap is two times more accurate. For example the default value is 8cm and the LM grid value per object equal to 0.5 result in a lightmap grid for object that is 4cm. The LM grid parameter can be separately set for each Block side.