diff options
Diffstat (limited to 'src/intersect/intersect.cpp')
| -rw-r--r-- | src/intersect/intersect.cpp | 48 |
1 files changed, 25 insertions, 23 deletions
diff --git a/src/intersect/intersect.cpp b/src/intersect/intersect.cpp index 69512e3..05a4d64 100644 --- a/src/intersect/intersect.cpp +++ b/src/intersect/intersect.cpp @@ -59,11 +59,11 @@ glm::vec4 intersectCone( isHit = false; float t = FINF; // updated to 4d - // x^2 + y^2 - z^2 - w^2= 0, conic top + // x^2 + z^2 - y^2 - w^2= r^2, conic top float radius = 0.5f; float a = d.x*d.x + d.z*d.z - .25f*(d.y*d.y) - .25f*(d[3]*d[3]); float b = 2.f*(p.x*d.x + p.z*d.z) - .5f*(p.y*d.y) + .25f*d.y - .5f*(p[3]*d[3]) + .25f*d[3]; - float c = p.x*p.x + p.z*p.z - .25f*(p.y*p.y) + .25f*p.y - .25f*(p[3]*p[3]) + .25f*p[3] - 1/8.f; + float c = p.x*p.x + p.z*p.z - .25f*(p.y*p.y) + .25f*p.y - .25f*(p[3]*p[3]) + .25f*p[3] - 1/16.f; float discriminant = b*b - 4*a*c; if (discriminant >= 0) @@ -97,18 +97,20 @@ glm::vec4 intersectCone( auto pwBase = p + twBase * d; if ( twBase > 0 && - pwBase.x*pwBase.x + pwBase.z*pwBase.z <= pwBase.y*pwBase.y + pwBase.x*pwBase.x + pwBase.z*pwBase.z <= pwBase.y*pwBase.y + .25f && + pwBase.y >= -.5f && pwBase.y <= .5f ) { t = std::min(t, twBase); } - // x^2 + y^2 - z^2 = 0, base w.r.t. y axis + // x^2 + w^2 - z^2 = 0, base w.r.t. y axis float tyBase = (- .5f - p.y) / d.y; auto pyBase = p + tyBase * d; if ( tyBase > 0 && - pyBase.x*pyBase.x + pyBase.z*pyBase.z <= pyBase[3]*pyBase[3] + pyBase.x*pyBase.x + pyBase.z*pyBase.z <= pyBase[3]*pyBase[3] + .25f && + pyBase[3] >= -.5f && pyBase[3] <= .5f ) { t = std::min(t, tyBase); @@ -132,11 +134,11 @@ glm::vec4 intersectCylinder( isHit = false; float t = FINF; - // implicit: x^2 + z^2 = r^2, y + w between -.5, .5 rectuangular side + // implicit: x^2 + z^2 - w/2 = r^2, y + w between -.5, .5 float radius = 0.5f; float a = d.x*d.x + d.z*d.z; - float b = 2.f * (p.x*d.x + p.z*d.z); - float c = p.x*p.x + p.z*p.z - radius*radius; + float b = 2.f * (p.x*d.x + p.z*d.z) - .5f * d[3]; + float c = p.x*p.x + p.z*p.z - .5f * p[3] - radius*radius; float discriminant = b*b - 4*a*c; if (discriminant >= 0) @@ -147,9 +149,9 @@ glm::vec4 intersectCylinder( auto p1Top = p + t1 * d; if ( t1 > 0 && - p1Top.y + p1Top[3] >= -.5f && p1Top.y + p1Top[3] <= .5f && - p1Top.y >= -.5f && p1Top.y <= .5f && - p1Top[3] >= -.5f && p1Top[3] <= .5f) + p1Top.y + p1Top[3] >= -.5f && p1Top.y - p1Top[3] <= .5f && + p1Top[3] >= -.5f && p1Top[3] <= .5f + ) { t = std::min(t1, t); } @@ -157,8 +159,7 @@ glm::vec4 intersectCylinder( auto p2Top = p + t2 * d; if ( t2 > 0 && - p2Top.y + p2Top[3] >= -.5f && p2Top.y + p2Top[3] <= .5f && - p2Top.y >= -.5f && p2Top.y <= .5f && + p2Top.y + p2Top[3] >= -.5f && p2Top.y - p2Top[3] <= .5f && p2Top[3] >= -.5f && p2Top[3] <= .5f) { t = std::min(t2, t); @@ -166,27 +167,28 @@ glm::vec4 intersectCylinder( } - // implicit y + w = .5f, top base - float tTop = (.5f - p.y - p[3]) / (d[3] + d.y); + // implicit y - w = .5f, top base + + float tTop = (.5f - p.y + p[3]) / (d.y - d[3]); auto pTop = p + tTop * d; if ( tTop > 0 && - pTop.x*pTop.x + pTop.z*pTop.z <= radius*radius && - pTop.y >= -.5f && pTop.y <= .5f && - pTop[3] >= -.5f && pTop[3] <= .5f) + pTop.x*pTop.x + pTop.z*pTop.z <= radius*radius + pTop[3]/2.f && + pTop[3] >= -.5f && pTop[3] <= .5f + ) { t = std::min(t, tTop); } - // implicit p_y + t*d_y = -.5f, Bottom base - float tBase = (.5f - p.y - p[3]) / (d[3] + d.y); + // implicit y + w = -.5f, Bottom base + float tBase = (-.5f - p.y - p[3]) / (d[3] + d.y); auto pBase = p + tBase * d; if ( tBase > 0 && - pBase.x*pBase.x + pBase.z*pBase.z <= radius*radius && - pBase.y >= -.5f && pBase.y <= .5f && - pBase[3] >= -.5f && pBase[3] <= .5f) + pBase.x*pBase.x + pBase.z*pBase.z <= radius*radius + pBase[3]/2.f && + pBase[3] >= -.5f && pBase[3] <= .5f + ) { t = std::min(t, tBase); } |