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Diffstat (limited to 'rwsdk/include/d3d8/rtintsec.h')
| -rw-r--r-- | rwsdk/include/d3d8/rtintsec.h | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/rwsdk/include/d3d8/rtintsec.h b/rwsdk/include/d3d8/rtintsec.h new file mode 100644 index 00000000..cb482b17 --- /dev/null +++ b/rwsdk/include/d3d8/rtintsec.h @@ -0,0 +1,138 @@ +/*************************************************************************** + * * + * Module : rtintsec.h * + * * + * Purpose : Intersection tests on geometry primitives. * + * * + **************************************************************************/ + +#ifndef RTINTSEC_H +#define RTINTSEC_H + +/** + * \defgroup rtintersect RtIntersection + * \ingroup rttool + * + * Object Intersection Toolkit for RenderWare. + */ + +/**************************************************************************** + Includes + */ + +#include <rwcore.h> +#include "rtintsec.rpe" /* automatically generated header file */ + +/**************************************************************************** + Defines + */ + +#define RTINTSECEPSILON (RwReal)(1e-8) +#define RTINTSECEDGEEPS (RwReal)(1e-5) + +#define RtIntersectionLineTriangleMacro(_result, \ + _lineStart, _lineDelta, \ + _v0, _v1, _v2, \ + _distance) \ +MACRO_START \ +{ \ + RwV3d edge1, edge2, tVec, pVec, qVec; \ + RwReal det; \ + \ + /* Find vectors for two edges sharing vert0 */ \ + RwV3dSubMacro(&edge1, (_v1), (_v0)); \ + RwV3dSubMacro(&edge2, (_v2), (_v0)); \ + \ + /* Begin calculating determinant \ + * - also used to calculate U parameter */ \ + RwV3dCrossProductMacro(&pVec, (_lineDelta), &edge2); \ + \ + /* If determinant is \ + * + near zero, ray lies in plane of \ + * triangle \ + * + negative, triangle is backfacing \ + */ \ + det = RwV3dDotProductMacro(&edge1, &pVec); \ + (_result) = (det > RTINTSECEPSILON); \ + \ + if ((_result)) \ + { \ + RwReal lo, hi, u; \ + \ + /* Calculate bounds for parameters with tolerance */ \ + lo = - det*RTINTSECEDGEEPS; \ + hi = det - lo; \ + \ + /* Calculate U parameter and test bounds */ \ + RwV3dSubMacro(&tVec, (_lineStart), (_v0)); \ + u = RwV3dDotProductMacro(&tVec, &pVec); \ + (_result) = (u >= lo && u <= hi); \ + \ + if ((_result)) \ + { \ + RwReal v; \ + \ + /* Calculate V parameter and test bounds */ \ + RwV3dCrossProductMacro(&qVec, &tVec, &edge1); \ + v = RwV3dDotProductMacro((_lineDelta), &qVec); \ + (_result) = (v >= lo && (u + v) <= hi); \ + \ + if ((_result)) \ + { \ + /* Calculate t, \ + * and make sure intersection is in bounds of line */ \ + *(_distance) = RwV3dDotProductMacro(&edge2, &qVec); \ + \ + /* Within bounds of line? */ \ + (_result) = (*(_distance) >= lo && *(_distance) <= hi); \ + \ + if ((_result)) \ + { \ + *(_distance) = ((*(_distance)) / (det)); \ + } \ + } \ + } \ + } \ +} \ +MACRO_STOP + + +/**************************************************************************** + Global Types + */ + + +/* RWPUBLIC */ +/**************************************************************************** + Function prototypes + */ + +#ifdef __cplusplus +extern "C" +{ +#endif /* __cplusplus */ + +/* Line intersections */ +extern RwBool +RtIntersectionLineTriangle(RwV3d *lineStart, RwV3d *lineDelta, + RwV3d *v0, RwV3d *v1, RwV3d *v2, + RwReal *distance); + +/* Sphere intersections */ +extern RwBool +RtIntersectionSphereTriangle(RwSphere *sphere, + RwV3d *v0, RwV3d *v1, RwV3d *v2, + RwV3d *normal, + RwReal *distance); + +/* BBox intersections */ +extern RwBool +RtIntersectionBBoxTriangle(RwBBox *bbox, RwV3d *v0, RwV3d *v1, RwV3d *v2); + +#ifdef __cplusplus +} +#endif /* __cplusplus */ + +/* RWPUBLICEND */ + +#endif /* RTINTSEC_H */ |