diff options
Diffstat (limited to 'src/rtw')
| -rw-r--r-- | src/rtw/hittable.zig | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/src/rtw/hittable.zig b/src/rtw/hittable.zig index 5f1bca6..b0bedf8 100644 --- a/src/rtw/hittable.zig +++ b/src/rtw/hittable.zig @@ -34,6 +34,8 @@ const HittableTag = enum { list, bvhNode, xyRect, + xzRect, + yzRect, }; pub const Hittable = union(HittableTag) { @@ -42,6 +44,8 @@ pub const Hittable = union(HittableTag) { list: HittableList, bvhNode: BvhNode, xyRect: XyRect, + xzRect: XzRect, + yzRect: YzRect, pub fn hit(h: Hittable, r: Ray, tMin: f64, tMax: f64, record: *HitRecord) bool { return switch (h) { @@ -50,6 +54,8 @@ pub const Hittable = union(HittableTag) { HittableTag.list => |list| list.hit(r, tMin, tMax, record), HittableTag.bvhNode => |node| node.hit(r, tMin, tMax, record), HittableTag.xyRect => |rect| rect.hit(r, tMin, tMax, record), + HittableTag.xzRect => |rect| rect.hit(r, tMin, tMax, record), + HittableTag.yzRect => |rect| rect.hit(r, tMin, tMax, record), }; } @@ -60,6 +66,8 @@ pub const Hittable = union(HittableTag) { HittableTag.list => |list| list.boudingBox(time0, time1, outputBox), HittableTag.bvhNode => |node| node.boudingBox(time0, time1, outputBox), HittableTag.xyRect => |rect| rect.boudingBox(time0, time1, outputBox), + HittableTag.xzRect => |rect| rect.boudingBox(time0, time1, outputBox), + HittableTag.yzRect => |rect| rect.boudingBox(time0, time1, outputBox), }; } @@ -70,6 +78,8 @@ pub const Hittable = union(HittableTag) { HittableTag.list => |list| list.deinit(allocator), HittableTag.bvhNode => |node| node.deinit(allocator), HittableTag.xyRect => |rect| rect.deinit(allocator), + HittableTag.xzRect => |rect| rect.deinit(allocator), + HittableTag.yzRect => |rect| rect.deinit(allocator), }; } }; @@ -392,3 +402,111 @@ const XyRect = struct { _ = allocator; } }; + +const XzRect = struct { + x0: f64, + x1: f64, + z0: f64, + z1: f64, + k: f64, + material: *const Material, + + pub fn hit(rect: XzRect, r: Ray, tMin: f64, tMax: f64, record: *HitRecord) bool { + const t = (rect.k - r.origin.y) / r.dir.y; + if (t < tMin or t > tMax) { + return false; + } + const x = r.origin.x + t * r.dir.x; + const z = r.origin.z + t * r.dir.z; + if (x < rect.x0 or x > rect.x1 or z < rect.z0 or z > rect.z1) { + return false; + } + + record.u = (x - rect.x0) / (rect.x1 - rect.x0); + record.v = (z - rect.z0) / (rect.z1 - rect.z0); + record.t = t; + record.material = rect.material; + record.p = r.at(t); + + const outward_normal = Vec3{ .x = 0, .y = 1, .z = 0 }; + record.front_face = Vec3.dot(outward_normal, r.dir) < 0.0; + if (record.front_face) { + record.normal = outward_normal; + } else { + record.normal = outward_normal.mul(-1.0); + } + return true; + } + + pub fn boudingBox(rect: XzRect, time0: f64, time1: f64, outputBox: *Aabb) bool { + _ = time0; + _ = time1; + + // The bounding box must have non-zero width in each dimension, so pad the Y + // dimension a small amount. + outputBox.* = .{ + .min = Point3.init(rect.x0, rect.k - 0.0001, rect.z0), + .max = Point3.init(rect.x1, rect.k + 0.0001, rect.z1), + }; + return true; + } + + pub fn deinit(rect: *const XzRect, allocator: anytype) void { + _ = rect; + _ = allocator; + } +}; + +const YzRect = struct { + y0: f64, + y1: f64, + z0: f64, + z1: f64, + k: f64, + material: *const Material, + + pub fn hit(rect: YzRect, r: Ray, tMin: f64, tMax: f64, record: *HitRecord) bool { + const t = (rect.k - r.origin.x) / r.dir.x; + if (t < tMin or t > tMax) { + return false; + } + const y = r.origin.y + t * r.dir.y; + const z = r.origin.z + t * r.dir.z; + if (y < rect.y0 or y > rect.y1 or z < rect.z0 or z > rect.z1) { + return false; + } + + record.u = (y - rect.y0) / (rect.y1 - rect.y0); + record.v = (z - rect.z0) / (rect.z1 - rect.z0); + record.t = t; + record.material = rect.material; + record.p = r.at(t); + + const outward_normal = Vec3{ .x = 1, .y = 0, .z = 0 }; + record.front_face = Vec3.dot(outward_normal, r.dir) < 0.0; + if (record.front_face) { + record.normal = outward_normal; + } else { + record.normal = outward_normal.mul(-1.0); + } + return true; + } + + pub fn boudingBox(rect: YzRect, time0: f64, time1: f64, outputBox: *Aabb) bool { + _ = time0; + _ = time1; + + // The bounding box must have non-zero width in each dimension, so pad the X + // dimension a small amount. + outputBox.* = .{ + .min = Point3.init(rect.k - 0.0001, rect.y0, rect.z0), + .max = Point3.init(rect.k + 0.0001, rect.y1, rect.z1), + }; + return true; + } + + pub fn deinit(rect: *const YzRect, allocator: anytype) void { + _ = rect; + _ = allocator; + } +}; |