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RtIntersection
[Math Tools]

Functions
RwBool	RtIntersectionLineTriangle (const RwV3d *lineStart, const RwV3d *lineDelta, const RwV3d *v0, const RwV3d *v1, const RwV3d *v2, RwReal *distance)
RwBool	RtIntersectionSphereTriangle (const RwSphere *sphere, const RwV3d *v0, const RwV3d *v1, const RwV3d *v2, RwV3d *normal, RwReal *distance)
RwBool	RtIntersectionBBoxTriangle (const RwBBox *bbox, const RwV3d *v0, const RwV3d *v1, const RwV3d *v2)

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Detailed Description

Object Intersection Toolkit for RenderWare.

RtIntersection Toolkit Overview

Requirements

• Headers: rwcore.h, rtintsec.h
• Libraries: rwcore, rtintsec
• Plugin attachments: None

Overview

This toolkit provides functions for testing whether certain geometry primitives intersect. The following are provided:

• RtIntersectionLineTriangle tests whether a given line intersects a given triangle.
• RtIntersectionSphereTriangle tests whether a given sphere intersects a given triangle.
• RtIntersectionBBoxTriangle tests whether a given bounding box intersections a given triangle.

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Function Documentation

RwBool RtIntersectionBBoxTriangle (  const RwBBox *    bbox, const RwV3d *    v0, const RwV3d *    v1, const RwV3d *    v2 )

RtIntersectionBBoxTriangle tests for the intersection of a bounding box with a triangle. Parameters: bbox  Bounding box v0  Triangle vertex 0 v1  Triangle vertex 1 v2  Triangle vertex 2 Returns: Returns TRUE if an intersection is found, or FALSE otherwise.

RwBool RtIntersectionLineTriangle (  const RwV3d *    lineStart, const RwV3d *    lineDelta, const RwV3d *    v0, const RwV3d *    v1, const RwV3d *    v2, RwReal *    distance )

RtIntersectionLineTriangle tests for the intersection of a line with a triangle, and if found, returns the parametric distance to the intersection along the line. This function returns TRUE if the line, specified at the starting point lineStart (RwV3d) and a lineDelta (RwV3d) defining the displacement vector, intersects with the triangle (RwV3d). The lineDelta parameter is used to reduce calculation overheads when processing a large number of triangles and can be obtained from RwV3dSub(lineDelta, &line.end, &line.start). This function also takes another parameter, distance, which will hold the parametric distance to the intersection if an intersection was found. This function use backface culling which means: the order of the triangle vertices is very important you will need to make two calls for two-sided tests Parameters: lineStart  Line start vertex lineDelta  Line displacement vector v0  Triangle vertex 0 v1  Triangle vertex 1 v2  Triangle vertex 2 distance  On return, contains parameteric distance to intersection Returns: Returns TRUE if an intersection is found, or FALSE otherwise.

RwBool RtIntersectionSphereTriangle (  const RwSphere *    sphere, const RwV3d *    v0, const RwV3d *    v1, const RwV3d *    v2, RwV3d *    normal, RwReal *    distance )

RtIntersectionSphereTriangle tests for the intersection of a sphere with a triangle, and if found, returns the triangle normal and the perpendicular distance of the sphere center from the plane of the triangle. Parameters: sphere  Sphere v0  Triangle vertex 0 v1  Triangle vertex 1 v2  Triangle vertex 2 normal  If intersection is found, returns triangle normal distance  If intersection is found, returns distance of sphere center from the plane of the triangle Returns: Returns TRUE if an intersection is found, or FALSE otherwise.

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