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Diffstat (limited to 'modules/mono/glue/GodotSharp/GodotSharp/Core/Projection.cs')
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diff --git a/modules/mono/glue/GodotSharp/GodotSharp/Core/Projection.cs b/modules/mono/glue/GodotSharp/GodotSharp/Core/Projection.cs new file mode 100644 index 0000000000..d774021131 --- /dev/null +++ b/modules/mono/glue/GodotSharp/GodotSharp/Core/Projection.cs @@ -0,0 +1,820 @@ +#if REAL_T_IS_DOUBLE +using real_t = System.Double; +#else +using real_t = System.Single; +#endif +using System; +using System.Runtime.InteropServices; + +namespace Godot +{ + [Serializable] + [StructLayout(LayoutKind.Sequential)] + public struct Projection : IEquatable<Projection> + { + /// <summary> + /// Enumerated index values for the planes. + /// </summary> + public enum Planes + { + /// <summary> + /// The projection's near plane. + /// </summary> + Near, + /// <summary> + /// The projection's far plane. + /// </summary> + Far, + /// <summary> + /// The projection's left plane. + /// </summary> + Left, + /// <summary> + /// The projection's top plane. + /// </summary> + Top, + /// <summary> + /// The projection's right plane. + /// </summary> + Right, + /// <summary> + /// The projection's bottom plane. + /// </summary> + Bottom, + } + + /// <summary> + /// The projections's X column. Also accessible by using the index position <c>[0]</c>. + /// </summary> + public Vector4 x; + + /// <summary> + /// The projections's Y column. Also accessible by using the index position <c>[1]</c>. + /// </summary> + public Vector4 y; + + /// <summary> + /// The projections's Z column. Also accessible by using the index position <c>[2]</c>. + /// </summary> + public Vector4 z; + + /// <summary> + /// The projections's W column. Also accessible by using the index position <c>[3]</c>. + /// </summary> + public Vector4 w; + + /// <summary> + /// Constructs a projection from 4 vectors (matrix columns). + /// </summary> + /// <param name="x">The X column, or column index 0.</param> + /// <param name="y">The Y column, or column index 1.</param> + /// <param name="z">The Z column, or column index 2.</param> + /// <param name="w">The W column, or column index 3.</param> + public Projection(Vector4 x, Vector4 y, Vector4 z, Vector4 w) + { + this.x = x; + this.y = y; + this.z = z; + this.w = w; + } + + /// <summary> + /// Constructs a new <see cref="Projection"/> from an existing <see cref="Projection"/>. + /// </summary> + /// <param name="proj">The existing <see cref="Projection"/>.</param> + public Projection(Projection proj) + { + x = proj.x; + y = proj.y; + z = proj.z; + w = proj.w; + } + + /// <summary> + /// Constructs a new <see cref="Projection"/> from a <see cref="Transform3D"/>. + /// </summary> + /// <param name="transform">The <see cref="Transform3D"/>.</param> + public Projection(Transform3D transform) + { + x = new Vector4(transform.basis.Row0.x, transform.basis.Row1.x, transform.basis.Row2.x, 0); + y = new Vector4(transform.basis.Row0.y, transform.basis.Row1.y, transform.basis.Row2.y, 0); + z = new Vector4(transform.basis.Row0.z, transform.basis.Row1.z, transform.basis.Row2.z, 0); + w = new Vector4(transform.origin.x, transform.origin.y, transform.origin.z, 1); + } + + /// <summary> + /// Constructs a new <see cref="Transform3D"/> from the <see cref="Projection"/>. + /// </summary> + /// <param name="proj">The <see cref="Projection"/>.</param> + public static explicit operator Transform3D(Projection proj) + { + return new Transform3D( + new Basis( + new Vector3(proj.x.x, proj.x.y, proj.x.z), + new Vector3(proj.y.x, proj.y.y, proj.y.z), + new Vector3(proj.z.x, proj.z.y, proj.z.z) + ), + new Vector3(proj.w.x, proj.w.y, proj.w.z) + ); + } + + public static Projection CreateDepthCorrection(bool flipY) + { + return new Projection( + new Vector4(1, 0, 0, 0), + new Vector4(0, flipY ? -1 : 1, 0, 0), + new Vector4(0, 0, (real_t)0.5, 0), + new Vector4(0, 0, (real_t)0.5, 1) + ); + } + + public static Projection CreateFitAabb(AABB aabb) + { + Vector3 min = aabb.Position; + Vector3 max = aabb.Position + aabb.Size; + + return new Projection( + new Vector4(2 / (max.x - min.x), 0, 0, 0), + new Vector4(0, 2 / (max.y - min.y), 0, 0), + new Vector4(0, 0, 2 / (max.z - min.z), 0), + new Vector4(-(max.x + min.x) / (max.x - min.x), -(max.y + min.y) / (max.y - min.y), -(max.z + min.z) / (max.z - min.z), 1) + ); + } + + public static Projection CreateForHmd(int eye, real_t aspect, real_t intraocularDist, real_t displayWidth, real_t displayToLens, real_t oversample, real_t zNear, real_t zFar) + { + real_t f1 = (intraocularDist * (real_t)0.5) / displayToLens; + real_t f2 = ((displayWidth - intraocularDist) * (real_t)0.5) / displayToLens; + real_t f3 = (displayWidth / (real_t)4.0) / displayToLens; + + real_t add = ((f1 + f2) * (oversample - (real_t)1.0)) / (real_t)2.0; + f1 += add; + f2 += add; + f3 *= oversample; + + f3 /= aspect; + + switch (eye) + { + case 1: + return CreateFrustum(-f2 * zNear, f1 * zNear, -f3 * zNear, f3 * zNear, zNear, zFar); + case 2: + return CreateFrustum(-f1 * zNear, f2 * zNear, -f3 * zNear, f3 * zNear, zNear, zFar); + default: + return Zero; + } + } + + public static Projection CreateFrustum(real_t left, real_t right, real_t bottom, real_t top, real_t near, real_t far) + { + if (right <= left) + { + throw new ArgumentException("right is less or equal to left."); + } + if (top <= bottom) + { + throw new ArgumentException("top is less or equal to bottom."); + } + if (far <= near) + { + throw new ArgumentException("far is less or equal to near."); + } + + real_t x = 2 * near / (right - left); + real_t y = 2 * near / (top - bottom); + + real_t a = (right + left) / (right - left); + real_t b = (top + bottom) / (top - bottom); + real_t c = -(far + near) / (far - near); + real_t d = -2 * far * near / (far - near); + + return new Projection( + new Vector4(x, 0, 0, 0), + new Vector4(0, y, 0, 0), + new Vector4(a, b, c, -1), + new Vector4(0, 0, d, 0) + ); + } + + public static Projection CreateFrustumAspect(real_t size, real_t aspect, Vector2 offset, real_t near, real_t far, bool flipFov) + { + if (!flipFov) + { + size *= aspect; + } + return CreateFrustum(-size / 2 + offset.x, +size / 2 + offset.x, -size / aspect / 2 + offset.y, +size / aspect / 2 + offset.y, near, far); + } + + public static Projection CreateLightAtlasRect(Rect2 rect) + { + return new Projection( + new Vector4(rect.Size.x, 0, 0, 0), + new Vector4(0, rect.Size.y, 0, 0), + new Vector4(0, 0, 1, 0), + new Vector4(rect.Position.x, rect.Position.y, 0, 1) + ); + } + + public static Projection CreateOrthogonal(real_t left, real_t right, real_t bottom, real_t top, real_t zNear, real_t zFar) + { + Projection proj = Projection.Identity; + proj.x.x = (real_t)2.0 / (right - left); + proj.w.x = -((right + left) / (right - left)); + proj.y.y = (real_t)2.0 / (top - bottom); + proj.w.y = -((top + bottom) / (top - bottom)); + proj.z.z = (real_t)(-2.0) / (zFar - zNear); + proj.w.z = -((zFar + zNear) / (zFar - zNear)); + proj.w.w = (real_t)1.0; + return proj; + } + + public static Projection CreateOrthogonalAspect(real_t size, real_t aspect, real_t zNear, real_t zFar, bool flipFov) + { + if (!flipFov) + { + size *= aspect; + } + return CreateOrthogonal(-size / 2, +size / 2, -size / aspect / 2, +size / aspect / 2, zNear, zFar); + } + + public static Projection CreatePerspective(real_t fovyDegrees, real_t aspect, real_t zNear, real_t zFar, bool flipFov) + { + if (flipFov) + { + fovyDegrees = GetFovy(fovyDegrees, (real_t)1.0 / aspect); + } + real_t radians = Mathf.Deg2Rad(fovyDegrees / (real_t)2.0); + real_t deltaZ = zFar - zNear; + real_t sine = Mathf.Sin(radians); + + if ((deltaZ == 0) || (sine == 0) || (aspect == 0)) + { + return Zero; + } + + real_t cotangent = Mathf.Cos(radians) / sine; + + Projection proj = Projection.Identity; + + proj.x.x = cotangent / aspect; + proj.y.y = cotangent; + proj.z.z = -(zFar + zNear) / deltaZ; + proj.z.w = -1; + proj.w.z = -2 * zNear * zFar / deltaZ; + proj.w.w = 0; + + return proj; + } + + public static Projection CreatePerspectiveHmd(real_t fovyDegrees, real_t aspect, real_t zNear, real_t zFar, bool flipFov, int eye, real_t intraocularDist, real_t convergenceDist) + { + if (flipFov) + { + fovyDegrees = GetFovy(fovyDegrees, (real_t)1.0 / aspect); + } + + real_t ymax = zNear * Mathf.Tan(Mathf.Deg2Rad(fovyDegrees / (real_t)2.0)); + real_t xmax = ymax * aspect; + real_t frustumshift = (intraocularDist / (real_t)2.0) * zNear / convergenceDist; + real_t left; + real_t right; + real_t modeltranslation; + switch (eye) + { + case 1: + left = -xmax + frustumshift; + right = xmax + frustumshift; + modeltranslation = intraocularDist / (real_t)2.0; + break; + case 2: + left = -xmax - frustumshift; + right = xmax - frustumshift; + modeltranslation = -intraocularDist / (real_t)2.0; + break; + default: + left = -xmax; + right = xmax; + modeltranslation = (real_t)0.0; + break; + } + Projection proj = CreateFrustum(left, right, -ymax, ymax, zNear, zFar); + Projection cm = Projection.Identity; + cm.w.x = modeltranslation; + return proj * cm; + } + + public real_t Determinant() + { + return x.w * y.z * z.y * w.x - x.z * y.w * z.y * w.x - + x.w * y.y * z.z * w.x + x.y * y.w * z.z * w.x + + x.z * y.y * z.w * w.x - x.y * y.z * z.w * w.x - + x.w * y.z * z.x * w.y + x.z * y.w * z.x * w.y + + x.w * y.x * z.z * w.y - x.x * y.w * z.z * w.y - + x.z * y.x * z.w * w.y + x.x * y.z * z.w * w.y + + x.w * y.y * z.x * w.z - x.y * y.w * z.x * w.z - + x.w * y.x * z.y * w.z + x.x * y.w * z.y * w.z + + x.y * y.x * z.w * w.z - x.x * y.y * z.w * w.z - + x.z * y.y * z.x * w.w + x.y * y.z * z.x * w.w + + x.z * y.x * z.y * w.w - x.x * y.z * z.y * w.w - + x.y * y.x * z.z * w.w + x.x * y.y * z.z * w.w; + } + + public real_t GetAspect() + { + Vector2 vpHe = GetViewportHalfExtents(); + return vpHe.x / vpHe.y; + } + + public real_t GetFov() + { + Plane rightPlane = new Plane(x.w - x.x, y.w - y.x, z.w - z.x, -w.w + w.x).Normalized(); + if (z.x == 0 && z.y == 0) + { + return Mathf.Rad2Deg(Mathf.Acos(Mathf.Abs(rightPlane.Normal.x))) * (real_t)2.0; + } + else + { + Plane leftPlane = new Plane(x.w + x.x, y.w + y.x, z.w + z.x, w.w + w.x).Normalized(); + return Mathf.Rad2Deg(Mathf.Acos(Mathf.Abs(leftPlane.Normal.x))) + Mathf.Rad2Deg(Mathf.Acos(Mathf.Abs(rightPlane.Normal.x))); + } + } + + public static real_t GetFovy(real_t fovx, real_t aspect) + { + return Mathf.Rad2Deg(Mathf.Atan(aspect * Mathf.Tan(Mathf.Deg2Rad(fovx) * (real_t)0.5)) * (real_t)2.0); + } + + public real_t GetLodMultiplier() + { + if (IsOrthogonal()) + { + return GetViewportHalfExtents().x; + } + else + { + real_t zn = GetZNear(); + real_t width = GetViewportHalfExtents().x * (real_t)2.0; + return (real_t)1.0 / (zn / width); + } + } + + public int GetPixelsPerMeter(int forPixelWidth) + { + Vector3 result = Xform(new Vector3(1, 0, -1)); + + return (int)((result.x * (real_t)0.5 + (real_t)0.5) * forPixelWidth); + } + + public Plane GetProjectionPlane(Planes plane) + { + Plane newPlane = plane switch + { + Planes.Near => new Plane(x.w + x.z, y.w + y.z, z.w + z.z, w.w + w.z), + Planes.Far => new Plane(x.w - x.z, y.w - y.z, z.w - z.z, w.w - w.z), + Planes.Left => new Plane(x.w + x.x, y.w + y.x, z.w + z.x, w.w + w.x), + Planes.Top => new Plane(x.w - x.y, y.w - y.y, z.w - z.y, w.w - w.y), + Planes.Right => new Plane(x.w - x.x, y.w - y.x, z.w - z.x, w.w - w.x), + Planes.Bottom => new Plane(x.w + x.y, y.w + y.y, z.w + z.y, w.w + w.y), + _ => new Plane(), + }; + newPlane.Normal = -newPlane.Normal; + return newPlane.Normalized(); + } + + public Vector2 GetFarPlaneHalfExtents() + { + var res = GetProjectionPlane(Planes.Far).Intersect3(GetProjectionPlane(Planes.Right), GetProjectionPlane(Planes.Top)); + return new Vector2(res.Value.x, res.Value.y); + } + + public Vector2 GetViewportHalfExtents() + { + var res = GetProjectionPlane(Planes.Near).Intersect3(GetProjectionPlane(Planes.Right), GetProjectionPlane(Planes.Top)); + return new Vector2(res.Value.x, res.Value.y); + } + + public real_t GetZFar() + { + return GetProjectionPlane(Planes.Far).D; + } + + public real_t GetZNear() + { + return -GetProjectionPlane(Planes.Near).D; + } + + public Projection FlippedY() + { + Projection proj = this; + proj.y = -proj.y; + return proj; + } + + public Projection PerspectiveZNearAdjusted(real_t newZNear) + { + Projection proj = this; + real_t zFar = GetZFar(); + real_t zNear = newZNear; + real_t deltaZ = zFar - zNear; + proj.z.z = -(zFar + zNear) / deltaZ; + proj.w.z = -2 * zNear * zFar / deltaZ; + return proj; + } + + public Projection JitterOffseted(Vector2 offset) + { + Projection proj = this; + proj.w.x += offset.x; + proj.w.y += offset.y; + return proj; + } + + public Projection Inverse() + { + Projection proj = this; + int i, j, k; + int[] pvt_i = new int[4]; + int[] pvt_j = new int[4]; /* Locations of pivot matrix */ + real_t pvt_val; /* Value of current pivot element */ + real_t hold; /* Temporary storage */ + real_t determinant = 1.0f; + for (k = 0; k < 4; k++) + { + /* Locate k'th pivot element */ + pvt_val = proj[k][k]; /* Initialize for search */ + pvt_i[k] = k; + pvt_j[k] = k; + for (i = k; i < 4; i++) + { + for (j = k; j < 4; j++) + { + if (Mathf.Abs(proj[i][j]) > Mathf.Abs(pvt_val)) + { + pvt_i[k] = i; + pvt_j[k] = j; + pvt_val = proj[i][j]; + } + } + } + + /* Product of pivots, gives determinant when finished */ + determinant *= pvt_val; + if (Mathf.IsZeroApprox(determinant)) + { + return Zero; + } + + /* "Interchange" rows (with sign change stuff) */ + i = pvt_i[k]; + if (i != k) + { /* If rows are different */ + for (j = 0; j < 4; j++) + { + hold = -proj[k][j]; + proj[k, j] = proj[i][j]; + proj[i, j] = hold; + } + } + + /* "Interchange" columns */ + j = pvt_j[k]; + if (j != k) + { /* If columns are different */ + for (i = 0; i < 4; i++) + { + hold = -proj[i][k]; + proj[i, k] = proj[i][j]; + proj[i, j] = hold; + } + } + + /* Divide column by minus pivot value */ + for (i = 0; i < 4; i++) + { + if (i != k) + { + proj[i, k] /= (-pvt_val); + } + } + + /* Reduce the matrix */ + for (i = 0; i < 4; i++) + { + hold = proj[i][k]; + for (j = 0; j < 4; j++) + { + if (i != k && j != k) + { + proj[i, j] += hold * proj[k][j]; + } + } + } + + /* Divide row by pivot */ + for (j = 0; j < 4; j++) + { + if (j != k) + { + proj[k, j] /= pvt_val; + } + } + + /* Replace pivot by reciprocal (at last we can touch it). */ + proj[k, k] = (real_t)1.0 / pvt_val; + } + + /* That was most of the work, one final pass of row/column interchange */ + /* to finish */ + for (k = 4 - 2; k >= 0; k--) + { /* Don't need to work with 1 by 1 corner*/ + i = pvt_j[k]; /* Rows to swap correspond to pivot COLUMN */ + if (i != k) + { /* If rows are different */ + for (j = 0; j < 4; j++) + { + hold = proj[k][j]; + proj[k, j] = -proj[i][j]; + proj[i, j] = hold; + } + } + + j = pvt_i[k]; /* Columns to swap correspond to pivot ROW */ + if (j != k) + { /* If columns are different */ + for (i = 0; i < 4; i++) + { + hold = proj[i][k]; + proj[i, k] = -proj[i][j]; + proj[i, j] = hold; + } + } + } + return proj; + } + + public bool IsOrthogonal() + { + return w.w == (real_t)1.0; + } + + /// <summary> + /// Composes these two projections by multiplying them + /// together. This has the effect of applying the right + /// and then the left projection. + /// </summary> + /// <param name="left">The parent transform.</param> + /// <param name="right">The child transform.</param> + /// <returns>The composed projection.</returns> + public static Projection operator *(Projection left, Projection right) + { + return new Projection( + new Vector4( + left.x.x * right.x.x + left.y.x * right.x.y + left.z.x * right.x.z + left.w.x * right.x.w, + left.x.y * right.x.x + left.y.y * right.x.y + left.z.y * right.x.z + left.w.y * right.x.w, + left.x.z * right.x.x + left.y.z * right.x.y + left.z.z * right.x.z + left.w.z * right.x.w, + left.x.w * right.x.x + left.y.w * right.x.y + left.z.w * right.x.z + left.w.w * right.x.w + ), new Vector4( + left.x.x * right.y.x + left.y.x * right.y.y + left.z.x * right.y.z + left.w.x * right.y.w, + left.x.y * right.y.x + left.y.y * right.y.y + left.z.y * right.y.z + left.w.y * right.y.w, + left.x.z * right.y.x + left.y.z * right.y.y + left.z.z * right.y.z + left.w.z * right.y.w, + left.x.w * right.y.x + left.y.w * right.y.y + left.z.w * right.y.z + left.w.w * right.y.w + ), new Vector4( + left.x.x * right.z.x + left.y.x * right.z.y + left.z.x * right.z.z + left.w.x * right.z.w, + left.x.y * right.z.x + left.y.y * right.z.y + left.z.y * right.z.z + left.w.y * right.z.w, + left.x.z * right.z.x + left.y.z * right.z.y + left.z.z * right.z.z + left.w.z * right.z.w, + left.x.w * right.z.x + left.y.w * right.z.y + left.z.w * right.z.z + left.w.w * right.z.w + ), new Vector4( + left.x.x * right.w.x + left.y.x * right.w.y + left.z.x * right.w.z + left.w.x * right.w.w, + left.x.y * right.w.x + left.y.y * right.w.y + left.z.y * right.w.z + left.w.y * right.w.w, + left.x.z * right.w.x + left.y.z * right.w.y + left.z.z * right.w.z + left.w.z * right.w.w, + left.x.w * right.w.x + left.y.w * right.w.y + left.z.w * right.w.z + left.w.w * right.w.w + ) + ); + } + + /// <summary> + /// Returns a vector transformed (multiplied) by this projection. + /// </summary> + /// <param name="proj">The projection to apply.</param> + /// <param name="v">A vector to transform.</param> + /// <returns>The transformed vector.</returns> + public static Vector4 operator *(Projection proj, Vector4 v) + { + return new Vector4( + proj.x.x * v.x + proj.y.x * v.y + proj.z.x * v.z + proj.w.x * v.w, + proj.x.y * v.x + proj.y.y * v.y + proj.z.y * v.z + proj.w.y * v.w, + proj.x.z * v.x + proj.y.z * v.y + proj.z.z * v.z + proj.w.z * v.w, + proj.x.w * v.x + proj.y.w * v.y + proj.z.w * v.z + proj.w.w * v.w + ); + } + + /// <summary> + /// Returns <see langword="true"/> if the projections are exactly equal. + /// </summary> + /// <param name="left">The left projection.</param> + /// <param name="right">The right projection.</param> + /// <returns>Whether or not the projections are exactly equal.</returns> + public static bool operator ==(Projection left, Projection right) + { + return left.Equals(right); + } + + /// <summary> + /// Returns <see langword="true"/> if the projections are not exactly equal. + /// </summary> + /// <param name="left">The left projection.</param> + /// <param name="right">The right projection.</param> + /// <returns>Whether or not the projections are not exactly equal.</returns> + public static bool operator !=(Projection left, Projection right) + { + return !left.Equals(right); + } + + /// <summary> + /// Access whole columns in the form of <see cref="Vector4"/>. + /// </summary> + /// <param name="column">Which column vector.</param> + public Vector4 this[int column] + { + get + { + switch (column) + { + case 0: + return x; + case 1: + return y; + case 2: + return z; + case 3: + return w; + default: + throw new IndexOutOfRangeException(); + } + } + set + { + switch (column) + { + case 0: + x = value; + return; + case 1: + y = value; + return; + case 2: + z = value; + return; + case 3: + w = value; + return; + default: + throw new IndexOutOfRangeException(); + } + } + } + + /// <summary> + /// Access single values. + /// </summary> + /// <param name="column">Which column vector.</param> + /// <param name="row">Which row of the column.</param> + public real_t this[int column, int row] + { + get + { + switch (column) + { + case 0: + return x[row]; + case 1: + return y[row]; + case 2: + return z[row]; + case 3: + return w[row]; + default: + throw new IndexOutOfRangeException(); + } + } + set + { + switch (column) + { + case 0: + x[row] = value; + return; + case 1: + y[row] = value; + return; + case 2: + z[row] = value; + return; + case 3: + w[row] = value; + return; + default: + throw new IndexOutOfRangeException(); + } + } + } + + /// <summary> + /// Returns a vector transformed (multiplied) by this projection. + /// </summary> + /// <param name="v">A vector to transform.</param> + /// <returns>The transformed vector.</returns> + private Vector3 Xform(Vector3 v) + { + Vector3 ret = new Vector3( + x.x * v.x + y.x * v.y + z.x * v.z + w.x, + x.y * v.x + y.y * v.y + z.y * v.z + w.y, + x.z * v.x + y.z * v.y + z.z * v.z + w.z + ); + return ret / (x.w * v.x + y.w * v.y + z.w * v.z + w.w); + } + + // Constants + private static readonly Projection _zero = new Projection( + new Vector4(0, 0, 0, 0), + new Vector4(0, 0, 0, 0), + new Vector4(0, 0, 0, 0), + new Vector4(0, 0, 0, 0) + ); + private static readonly Projection _identity = new Projection( + new Vector4(1, 0, 0, 0), + new Vector4(0, 1, 0, 0), + new Vector4(0, 0, 1, 0), + new Vector4(0, 0, 0, 1) + ); + + /// <summary> + /// Zero projection, a projection with all components set to <c>0</c>. + /// </summary> + /// <value>Equivalent to <c>new Projection(Vector4.Zero, Vector4.Zero, Vector4.Zero, Vector4.Zero)</c>.</value> + public static Projection Zero { get { return _zero; } } + + /// <summary> + /// The identity projection, with no distortion applied. + /// This is used as a replacement for <c>Projection()</c> in GDScript. + /// Do not use <c>new Projection()</c> with no arguments in C#, because it sets all values to zero. + /// </summary> + /// <value>Equivalent to <c>new Projection(new Vector4(1, 0, 0, 0), new Vector4(0, 1, 0, 0), new Vector4(0, 0, 1, 0), new Vector4(0, 0, 0, 1))</c>.</value> + public static Projection Identity { get { return _identity; } } + + /// <summary> + /// Serves as the hash function for <see cref="Projection"/>. + /// </summary> + /// <returns>A hash code for this projection.</returns> + public override int GetHashCode() + { + return y.GetHashCode() ^ x.GetHashCode() ^ z.GetHashCode() ^ w.GetHashCode(); + } + + /// <summary> + /// Converts this <see cref="Projection"/> to a string. + /// </summary> + /// <returns>A string representation of this projection.</returns> + public override string ToString() + { + return $"{x.x}, {x.y}, {x.z}, {x.w}\n{y.x}, {y.y}, {y.z}, {y.w}\n{z.x}, {z.y}, {z.z}, {z.w}\n{w.x}, {w.y}, {w.z}, {w.w}\n"; + } + + /// <summary> + /// Converts this <see cref="Projection"/> to a string with the given <paramref name="format"/>. + /// </summary> + /// <returns>A string representation of this projection.</returns> + public string ToString(string format) + { + return $"{x.x.ToString(format)}, {x.y.ToString(format)}, {x.z.ToString(format)}, {x.w.ToString(format)}\n" + + $"{y.x.ToString(format)}, {y.y.ToString(format)}, {y.z.ToString(format)}, {y.w.ToString(format)}\n" + + $"{z.x.ToString(format)}, {z.y.ToString(format)}, {z.z.ToString(format)}, {z.w.ToString(format)}\n" + + $"{w.x.ToString(format)}, {w.y.ToString(format)}, {w.z.ToString(format)}, {w.w.ToString(format)}\n"; + } + + /// <summary> + /// Returns <see langword="true"/> if the projection is exactly equal + /// to the given object (<see paramref="obj"/>). + /// </summary> + /// <param name="obj">The object to compare with.</param> + /// <returns>Whether or not the vector and the object are equal.</returns> + public override bool Equals(object obj) + { + if (obj is Projection) + { + return Equals((Projection)obj); + } + return false; + } + + /// <summary> + /// Returns <see langword="true"/> if the projections are exactly equal. + /// </summary> + /// <param name="other">The other projection.</param> + /// <returns>Whether or not the projections are exactly equal.</returns> + public bool Equals(Projection other) + { + return x == other.x && y == other.y && z == other.z && w == other.w; + } + } +} |