OGLShadowMap

DEPRECATED. This shader is unsupported, but it may still get installed with Softimage to provide compatibility with older scenes that use it. It is recommended that you replace unsupported shaders in your scenes with equivalent shaders from the current Softimage shader library.

Shader Type: RealTime

Output: RealTime

NoteThis shader is no longer supported, and scenes using it will not display correctly.

The OGL Shadowmap uses a shadowmap algorithm to reproduce the shadows created by a single spotlight. The shadows are output to a buffer, and then projected onto the objects to which the shader is applied. Because it accurately reproduces any one spotlight's shadows, this shader is a useful tool for previewing shadows before you render a scene.

Although the shadowmap shader works like other OGL shaders, it is subject to a few restrictions, namely:

It can only be used with a spotlight.
It must be applied to a single material shared by all shadow casting, and shadow receiving objects.
It must be used in its own drawing pass. If you want to see shadows with other surface attributes, you have to blend the shadows with those attributes in a second pass.

Spotlight Parameters

Light ID	The OGL numeric ID for the light whose shadows are being rendered. If the correct shadows are not displayed in viewports where Realtime Shaders viewing mode is enabled, an incorrect light ID is the likely culprit. Enable the Show Frustum option (below), and switch from one light ID to the next until you see the frustum and shadows for the desired light.
Frustum Field of View	Adjusts the frustum of the spotlight specified by the LightID. This is similar to adjusting a spotlight's Cone Angle. Lower values produce a smaller spot while higher values produce a larger spot. For the shadow map shadows to match rendered shadows, the Frustum value must be the same as the spotlight's Cone Angle value. It's a good idea to link these parameters if you are going to modify them frequently.
Frustum Near/Far Plane	Similar to a camera's clipping planes, the near and far planes specify the range within which the spotlight is active.
Frustum Show Frustum	Displays a wireframe of the spotlight's frustum in any viewports where Realtime Shaders viewing mode is enabled. This is similar to displaying a spotlight's cone, but the cone's near and far planes are displayed as well.

PBuffer Parameters

The PBuffer parameters control the buffer to which the shadowmap is rendered.

Resolution	Specifies the resolution of the shadowmap. Higher values give a smoother result but take more time to render and consume more memory.
Show PBuffer	Displays the contents of the PBuffer in a separate window.
Output Capture PBuffer	When enabled, the content's of the PBuffer are written to a file.
Output Filename	If Capture PBuffer is enabled, this is where you specify the filename, path, and extension of the file to which the buffer is written. When you are capturing the PBuffer to a file, it is updated at every frame and the target file is overwritten. Over time, this can consume large amounts of memory and degrade performance.

Render Tree Usage:

The OGL Shadowmap shader should be connected in its own drawing pass. Because it is a draw type shader, you can connect directly to the target material's realtime input. However, as the shader does not have built-in blending functions, you must connect it to a draw shader (OGLDraw, for example) if you wish to blend the shadows with surface attributes defined in another pass.

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