The SEDRIS Data Representation Model
APPENDIX B - Constraints
Colour Mapping Restrictions

Definition

  1. The colour_mapping field of a <Colour> shall not be empty.

  2. The SE_CLR_MAPNG_LGT_RENDER_BHVR_PRIMARY and SE_CLR_MAPNG_LGT_RENDER_BHVR_SECONDARY flags may only be used for objects with < Light Rendering Properties>.

  3. The SE_CLR_MAPNG_LGT_RENDER_BHVR_PRIMARY flag may not be combined with any other SE_Colour_Mapping.

  4. The SE_CLR_MAPNG_LGT_RENDER_BHVR_SECONDARY flag may not be combined with any other SE_Colour_Mapping.

Rationale

A <Colour> specifies how it is applied to the objects that use it, so the colour_mapping shall not be empty.

The SE_CLR_MAPNG_LGT_RENDER_BHVR_PRIMARY and SE_CLR_MAPNG_LGT_RENDER_BHVR_SECONDARY flags specify the primary and secondary colours of a < Light Rendering Properties>'s < Light Rendering Behaviour>.

If a <Colour> applies to the <Light Rendering Behaviour> of an object's < Light Rendering Properties> rather than the object itself, it shall apply only to that < Light Rendering Behaviour>. In addition, the same < Colour> cannot be both the primary and the secondary colour of a <Light Rendering Behaviour>.

Example

  1. Consider a <Polygon> with 2 <Inline Colours> and an <Image Mapping Function>, where the <Image Mapping Function>'s method is set to SE_IMG_MAPNG_METH_BLEND.
    Each <Inline Colour> shall specify whether it is primary, image blend, or neither, and which side of the <Polygon> is affected, in order to determine how to combine the colours with the texture.

FAQs

See the comments for <Colour>, SE_Colour_Mapping, and <Image Mapping Function> for discussions of how colour_mapping is interpreted.


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Last updated: October 1, 2002 Copyright © 2002 SEDRIS™