X-Git-Url: http://git.localhorst.tv/?a=blobdiff_plain;f=src%2Fmodel%2Fgeometry.cpp;fp=src%2Fmodel%2Fgeometry.cpp;h=0000000000000000000000000000000000000000;hb=4fbf5a3c1b0e530706023f5fc4be2f68d30ea645;hp=a4ac5006d55a019544f122a035af5d98d21cf308;hpb=0d580658b896dfec07466c31ae4847455724ee95;p=blank.git diff --git a/src/model/geometry.cpp b/src/model/geometry.cpp deleted file mode 100644 index a4ac500..0000000 --- a/src/model/geometry.cpp +++ /dev/null @@ -1,211 +0,0 @@ -#include "geometry.hpp" - -#include -#include -#include -#include - - -namespace blank { - -glm::mat3 find_rotation(const glm::vec3 &a, const glm::vec3 &b) noexcept { - glm::vec3 v(cross(a, b)); - if (iszero(v)) { - // a and b are parallel - if (iszero(a - b)) { - // a and b are identical - return glm::mat3(1.0f); - } else { - // a and b are opposite - // create arbitrary unit vector perpendicular to a and - // rotate 180° around it - glm::vec3 arb(a); - if (std::abs(a.x - 1.0f) > std::numeric_limits::epsilon()) { - arb.x += 1.0f; - } else { - arb.y += 1.0f; - } - glm::vec3 axis(normalize(cross(a, arb))); - return glm::mat3(glm::rotate(PI, axis)); - } - } - float mv = length_squared(v); - float c = dot(a, b); - float f = (1 - c) / mv; - glm::mat3 vx(matrixCross3(v)); - return glm::mat3(1.0f) + vx + (pow2(vx) * f); -} - -bool Intersection( - const Ray &ray, - const AABB &aabb, - const glm::mat4 &M, - float *dist, - glm::vec3 *normal -) noexcept { - float t_min = 0.0f; - float t_max = std::numeric_limits::infinity(); - const glm::vec3 aabb_pos(M[3].x, M[3].y, M[3].z); - const glm::vec3 delta = aabb_pos - ray.orig; - - glm::vec3 t1(t_min, t_min, t_min), t2(t_max, t_max, t_max); - - for (int i = 0; i < 3; ++i) { - const glm::vec3 axis(M[i].x, M[i].y, M[i].z); - const float e = glm::dot(axis, delta); - const float f = glm::dot(axis, ray.dir); - - if (std::abs(f) > std::numeric_limits::epsilon()) { - t1[i] = (e + aabb.min[i]) / f; - t2[i] = (e + aabb.max[i]) / f; - - t_min = std::max(t_min, std::min(t1[i], t2[i])); - t_max = std::min(t_max, std::max(t1[i], t2[i])); - - if (t_max < t_min) { - return false; - } - } else { - if (aabb.min[i] - e > 0.0f || aabb.max[i] - e < 0.0f) { - return false; - } - } - } - - glm::vec3 min_all(min(t1, t2)); - - if (dist) { - *dist = t_min; - } - if (normal) { - if (min_all.x > min_all.y) { - if (min_all.x > min_all.z) { - normal->x = t2.x < t1.x ? 1 : -1; - } else { - normal->z = t2.z < t1.z ? 1 : -1; - } - } else if (min_all.y > min_all.z) { - normal->y = t2.y < t1.y ? 1 : -1; - } else { - normal->z = t2.z < t1.z ? 1 : -1; - } - } - return true; -} - - -bool Intersection( - const AABB &a_box, - const glm::mat4 &a_m, - const AABB &b_box, - const glm::mat4 &b_m, - float &depth, - glm::vec3 &normal -) noexcept { - glm::vec3 a_corners[8] = { - glm::vec3(a_m * glm::vec4(a_box.min.x, a_box.min.y, a_box.min.z, 1)), - glm::vec3(a_m * glm::vec4(a_box.min.x, a_box.min.y, a_box.max.z, 1)), - glm::vec3(a_m * glm::vec4(a_box.min.x, a_box.max.y, a_box.min.z, 1)), - glm::vec3(a_m * glm::vec4(a_box.min.x, a_box.max.y, a_box.max.z, 1)), - glm::vec3(a_m * glm::vec4(a_box.max.x, a_box.min.y, a_box.min.z, 1)), - glm::vec3(a_m * glm::vec4(a_box.max.x, a_box.min.y, a_box.max.z, 1)), - glm::vec3(a_m * glm::vec4(a_box.max.x, a_box.max.y, a_box.min.z, 1)), - glm::vec3(a_m * glm::vec4(a_box.max.x, a_box.max.y, a_box.max.z, 1)), - }; - - glm::vec3 b_corners[8] = { - glm::vec3(b_m * glm::vec4(b_box.min.x, b_box.min.y, b_box.min.z, 1)), - glm::vec3(b_m * glm::vec4(b_box.min.x, b_box.min.y, b_box.max.z, 1)), - glm::vec3(b_m * glm::vec4(b_box.min.x, b_box.max.y, b_box.min.z, 1)), - glm::vec3(b_m * glm::vec4(b_box.min.x, b_box.max.y, b_box.max.z, 1)), - glm::vec3(b_m * glm::vec4(b_box.max.x, b_box.min.y, b_box.min.z, 1)), - glm::vec3(b_m * glm::vec4(b_box.max.x, b_box.min.y, b_box.max.z, 1)), - glm::vec3(b_m * glm::vec4(b_box.max.x, b_box.max.y, b_box.min.z, 1)), - glm::vec3(b_m * glm::vec4(b_box.max.x, b_box.max.y, b_box.max.z, 1)), - }; - - glm::vec3 axes[6] = { - glm::vec3(a_m * glm::vec4(1, 0, 0, 0)), - glm::vec3(a_m * glm::vec4(0, 1, 0, 0)), - glm::vec3(a_m * glm::vec4(0, 0, 1, 0)), - glm::vec3(b_m * glm::vec4(1, 0, 0, 0)), - glm::vec3(b_m * glm::vec4(0, 1, 0, 0)), - glm::vec3(b_m * glm::vec4(0, 0, 1, 0)), - }; - - depth = std::numeric_limits::infinity(); - int min_axis = 0; - - int cur_axis = 0; - for (const glm::vec3 &axis : axes) { - float a_min = std::numeric_limits::infinity(); - float a_max = -std::numeric_limits::infinity(); - for (const glm::vec3 &corner : a_corners) { - float val = glm::dot(corner, axis); - a_min = std::min(a_min, val); - a_max = std::max(a_max, val); - } - - float b_min = std::numeric_limits::infinity(); - float b_max = -std::numeric_limits::infinity(); - for (const glm::vec3 &corner : b_corners) { - float val = glm::dot(corner, axis); - b_min = std::min(b_min, val); - b_max = std::max(b_max, val); - } - - if (a_max < b_min || b_max < a_min) return false; - - float overlap = std::min(a_max, b_max) - std::max(a_min, b_min); - if (overlap < depth) { - depth = overlap; - min_axis = cur_axis; - } - - ++cur_axis; - } - - normal = axes[min_axis]; - return true; -} - - -bool CullTest(const AABB &box, const glm::mat4 &MVP) noexcept { - // transform corners into clip space - glm::vec4 corners[8] = { - { box.min.x, box.min.y, box.min.z, 1.0f }, - { box.min.x, box.min.y, box.max.z, 1.0f }, - { box.min.x, box.max.y, box.min.z, 1.0f }, - { box.min.x, box.max.y, box.max.z, 1.0f }, - { box.max.x, box.min.y, box.min.z, 1.0f }, - { box.max.x, box.min.y, box.max.z, 1.0f }, - { box.max.x, box.max.y, box.min.z, 1.0f }, - { box.max.x, box.max.y, box.max.z, 1.0f }, - }; - for (glm::vec4 &corner : corners) { - corner = MVP * corner; - corner /= corner.w; - } - - int hits[6] = { 0, 0, 0, 0, 0, 0 }; - - // check how many corners lie outside - for (const glm::vec4 &corner : corners) { - if (corner.x > 1.0f) ++hits[0]; - if (corner.x < -1.0f) ++hits[1]; - if (corner.y > 1.0f) ++hits[2]; - if (corner.y < -1.0f) ++hits[3]; - if (corner.z > 1.0f) ++hits[4]; - if (corner.z < -1.0f) ++hits[5]; - } - - // if all corners are outside any given clip plane, the test is true - for (int hit : hits) { - if (hit == 8) return true; - } - - // otherwise the box might still get culled completely, but can't say for sure ;) - return false; -} - -}