split out new quaternion hlsl stuff over from hlsl path tracer example

keptsecret · keptsecret · commit 781df861c9cc · 2025-12-02T17:13:14.000+07:00
diff --git a/include/nbl/builtin/hlsl/math/quaternions.hlsl b/include/nbl/builtin/hlsl/math/quaternions.hlsl
@@ -0,0 +1,305 @@
+// Copyright (C) 2018-2025 - DevSH Graphics Programming Sp. z O.O.
+// This file is part of the "Nabla Engine".
+// For conditions of distribution and use, see copyright notice in nabla.h
+#ifndef _NBL_BUILTIN_HLSL_MATH_QUATERNIONS_INCLUDED_
+#define _NBL_BUILTIN_HLSL_MATH_QUATERNIONS_INCLUDED_
+
+#include "nbl/builtin/hlsl/cpp_compat.hlsl"
+#include "nbl/builtin/hlsl/tgmath.hlsl"
+
+namespace nbl
+{
+namespace hlsl
+{
+namespace math
+{
+
+template<typename T>
+struct truncated_quaternion
+{
+    using this_t = truncated_quaternion<T>;
+    using scalar_type = T;
+    using data_type = vector<T, 3>;
+
+    static this_t create()
+    {
+        this_t q;
+        q.data = data_type(0.0, 0.0, 0.0);
+        return q;
+    }
+
+    data_type data;
+};
+
+template <typename T>
+struct quaternion
+{
+    using this_t = quaternion<T>;
+    using scalar_type = T;
+    using data_type = vector<T, 4>;
+    using vector3_type = vector<T, 3>;
+    using matrix_type = matrix<T, 3, 3>;
+
+    using AsUint = typename unsigned_integer_of_size<sizeof(scalar_type)>::type;
+
+    static this_t create()
+    {
+        this_t q;
+        q.data = data_type(0.0, 0.0, 0.0, 1.0);
+        return q;
+    }
+    
+    static this_t create(scalar_type x, scalar_type y, scalar_type z, scalar_type w)
+    {
+        this_t q;
+        q.data = data_type(x, y, z, w);
+        return q;
+    }
+
+    static this_t create(NBL_CONST_REF_ARG(this_t) other)
+    {
+        return other;
+    }
+
+    // angle: Rotation angle expressed in radians.
+    // axis: Rotation axis, must be normalized.
+    static this_t create(scalar_type angle, const vector3_type axis)
+    {
+        this_t q;
+        const scalar_type sinTheta = hlsl::sin(angle * 0.5);
+        const scalar_type cosTheta = hlsl::cos(angle * 0.5);
+        q.data = data_type(axis * sinTheta, cosTheta);
+        return q;
+    }
+
+
+    static this_t create(scalar_type pitch, scalar_type yaw, scalar_type roll)
+    {
+        const scalar_type rollDiv2 = roll * scalar_type(0.5);
+        const scalar_type sr = hlsl::sin(rollDiv2);
+        const scalar_type cr = hlsl::cos(rollDiv2);
+
+        const scalar_type pitchDiv2 = pitch * scalar_type(0.5);
+        const scalar_type sp = hlsl::sin(pitchDiv2);
+        const scalar_type cp = hlsl::cos(pitchDiv2);
+
+        const scalar_type yawDiv2 = yaw * scalar_type(0.5);
+        const scalar_type sy = hlsl::sin(yawDiv2);
+        const scalar_type cy = hlsl::cos(yawDiv2);
+
+        this_t output;
+        output.data[0] = cr * sp * cy + sr * cp * sy; // x
+        output.data[1] = cr * cp * sy - sr * sp * cy; // y
+        output.data[2] = sr * cp * cy - cr * sp * sy; // z
+        output.data[3] = cr * cp * cy + sr * sp * sy; // w
+
+        return output;
+    }
+
+    static this_t create(NBL_CONST_REF_ARG(matrix_type) m)
+    {
+        const scalar_type m00 = m[0][0], m11 = m[1][1], m22 = m[2][2];
+        const scalar_type neg_m00 = bit_cast<scalar_type>(bit_cast<AsUint>(m00)^0x80000000u);
+        const scalar_type neg_m11 = bit_cast<scalar_type>(bit_cast<AsUint>(m11)^0x80000000u);
+        const scalar_type neg_m22 = bit_cast<scalar_type>(bit_cast<AsUint>(m22)^0x80000000u);
+        const data_type Qx = data_type(m00, m00, neg_m00, neg_m00);
+        const data_type Qy = data_type(m11, neg_m11, m11, neg_m11);
+        const data_type Qz = data_type(m22, neg_m22, neg_m22, m22);
+
+        const data_type tmp = hlsl::promote<data_type>(1.0) + Qx + Qy + Qz;
+        const data_type invscales = hlsl::promote<data_type>(0.5) / hlsl::sqrt(tmp);
+        const data_type scales = tmp * invscales * hlsl::promote<data_type>(0.5);
+
+        // TODO: speed this up
+        this_t retval;
+        if (tmp.x > scalar_type(0.0))
+        {
+            retval.data.x = (m[2][1] - m[1][2]) * invscales.x;
+            retval.data.y = (m[0][2] - m[2][0]) * invscales.x;
+            retval.data.z = (m[1][0] - m[0][1]) * invscales.x;
+            retval.data.w = scales.x;
+        }
+        else
+        {
+            if (tmp.y > scalar_type(0.0))
+            {
+                retval.data.x = scales.y;
+                retval.data.y = (m[0][1] + m[1][0]) * invscales.y;
+                retval.data.z = (m[2][0] + m[0][2]) * invscales.y;
+                retval.data.w = (m[2][1] - m[1][2]) * invscales.y;
+            }
+            else if (tmp.z > scalar_type(0.0))
+            {
+                retval.data.x = (m[0][1] + m[1][0]) * invscales.z;
+                retval.data.y = scales.z;
+                retval.data.z = (m[0][2] - m[2][0]) * invscales.z;
+                retval.data.w = (m[1][2] + m[2][1]) * invscales.z;
+            }
+            else
+            {
+                retval.data.x = (m[0][2] + m[2][0]) * invscales.w;
+                retval.data.y = (m[1][2] + m[2][1]) * invscales.w;
+                retval.data.z = scales.w;
+                retval.data.w = (m[1][0] - m[0][1]) * invscales.w;
+            }
+        }
+
+        retval.data = hlsl::normalize(retval.data);
+        return retval;
+    }
+
+    static this_t create(NBL_CONST_REF_ARG(truncated_quaternion<T>) first3Components)
+    {
+        this_t retval;
+        retval.data.xyz = first3Components.data;
+        retval.data.w = hlsl::sqrt(scalar_type(1.0) - hlsl::dot(first3Components.data, first3Components.data));
+        return retval;
+    }
+
+    this_t operator*(scalar_type scalar)
+    {
+        this_t output;
+        output.data = data * scalar;
+        return output;
+    }
+
+    this_t operator*(NBL_CONST_REF_ARG(this_t) other)
+    {
+        return this_t::create(
+            data.w * other.data.w - data.x * other.x - data.y * other.data.y - data.z * other.data.z,
+            data.w * other.data.x + data.x * other.w + data.y * other.data.z - data.z * other.data.y,
+            data.w * other.data.y - data.x * other.z + data.y * other.data.w + data.z * other.data.x,
+            data.w * other.data.z + data.x * other.y - data.y * other.data.x + data.z * other.data.w
+        );
+    }
+
+    static this_t lerp(const this_t start, const this_t end, const scalar_type fraction, const scalar_type totalPseudoAngle)
+    {
+        const AsUint negationMask = hlsl::bit_cast<AsUint>(totalPseudoAngle) & AsUint(0x80000000u);
+        const data_type adjEnd = hlsl::bit_cast<scalar_type>(hlsl::bit_cast<AsUint>(end.data) ^ negationMask);
+
+        this_t retval;
+        retval.data = hlsl::mix(start.data, adjEnd, fraction);
+        return retval;
+    }
+
+    static this_t lerp(const this_t start, const this_t end, const scalar_type fraction)
+    {
+        return lerp(start, end, fraction, hlsl::dot(start.data, end.data));
+    }
+
+    static scalar_type __adj_interpolant(const scalar_type angle, const scalar_type fraction, const scalar_type interpolantPrecalcTerm2, const scalar_type interpolantPrecalcTerm3)
+    {
+        const scalar_type A = scalar_type(1.0904) + angle * (scalar_type(-3.2452) + angle * (scalar_type(3.55645) - angle * scalar_type(1.43519)));
+        const scalar_type B = scalar_type(0.848013) + angle * (scalar_type(-1.06021) + angle * scalar_type(0.215638));
+        const scalar_type k = A * interpolantPrecalcTerm2 + B;
+        return fraction + interpolantPrecalcTerm3 * k;
+    }
+
+    static this_t flerp(const this_t start, const this_t end, const scalar_type fraction)
+    {
+        const scalar_type pseudoAngle = hlsl::dot(start.data,end.data);
+        const scalar_type interpolantPrecalcTerm = fraction - scalar_type(0.5);
+        const scalar_type interpolantPrecalcTerm3 = fraction * interpolantPrecalcTerm * (fraction - scalar_type(1.0));
+        const scalar_type adjFrac = __adj_interpolant(hlsl::abs(pseudoAngle),fraction,interpolantPrecalcTerm*interpolantPrecalcTerm,interpolantPrecalcTerm3);
+        
+        this_t retval = lerp(start,end,adjFrac,pseudoAngle);
+        retval.data = hlsl::normalize(retval.data);
+        return retval;
+    }
+
+    vector3_type transformVector(const vector3_type v)
+    {
+        scalar_type scale = hlsl::length(data);
+        vector3_type direction = data.xyz;
+        return v * scale + hlsl::cross(direction, v * data.w + hlsl::cross(direction, v)) * scalar_type(2.0);
+    }
+
+    matrix_type constructMatrix()
+    {
+        matrix_type mat;
+        mat[0] = data.yzx * data.ywz + data.zxy * data.zyw * vector3_type( 1.0, 1.0,-1.0);
+        mat[1] = data.yzx * data.xzw + data.zxy * data.wxz * vector3_type(-1.0, 1.0, 1.0);
+        mat[2] = data.yzx * data.wyx + data.zxy * data.xwy * vector3_type( 1.0,-1.0, 1.0);
+        mat[0][0] = scalar_type(0.5) - mat[0][0];
+        mat[1][1] = scalar_type(0.5) - mat[1][1];
+        mat[2][2] = scalar_type(0.5) - mat[2][2];
+        mat *= scalar_type(2.0);
+        return hlsl::transpose(mat);    // TODO: double check transpose?
+    }
+
+    static vector3_type slerp_delta(const vector3_type start, const vector3_type preScaledWaypoint, scalar_type cosAngleFromStart)
+    {
+        vector3_type planeNormal = hlsl::cross(start,preScaledWaypoint);
+    
+        cosAngleFromStart *= scalar_type(0.5);
+        const scalar_type sinAngle = hlsl::sqrt(scalar_type(0.5) - cosAngleFromStart);
+        const scalar_type cosAngle = hlsl::sqrt(scalar_type(0.5) + cosAngleFromStart);
+        
+        planeNormal *= sinAngle;
+        const vector3_type precompPart = hlsl::cross(planeNormal, start) * scalar_type(2.0);
+
+        return precompPart * cosAngle + hlsl::cross(planeNormal, precompPart);
+    }
+
+    this_t inverse()
+    {
+        this_t retval;
+        retval.data.x = bit_cast<scalar_type>(bit_cast<AsUint>(data.x)^0x80000000u);
+        retval.data.y = bit_cast<scalar_type>(bit_cast<AsUint>(data.y)^0x80000000u);
+        retval.data.z = bit_cast<scalar_type>(bit_cast<AsUint>(data.z)^0x80000000u);
+        retval.data.w = data.w;
+        return retval;
+    }
+
+    static this_t normalize(NBL_CONST_REF_ARG(this_t) q)
+    {
+        this_t retval;
+        retval.data = hlsl::normalize(q.data);
+        return retval;
+    }
+
+    data_type data;
+};
+
+}
+
+namespace impl
+{
+
+template<typename T>
+struct static_cast_helper<math::quaternion<T>, math::truncated_quaternion<T> >
+{
+    static inline math::quaternion<T> cast(math::truncated_quaternion<T> q)
+    {
+        return math::quaternion<T>::create(q);
+    }
+};
+
+template<typename T>
+struct static_cast_helper<math::truncated_quaternion<T>, math::quaternion<T> >
+{
+    static inline math::truncated_quaternion<T> cast(math::quaternion<T> q)
+    {
+        math::truncated_quaternion<T> t;
+        t.data.x = t.data.x;
+        t.data.y = t.data.y;
+        t.data.z = t.data.z;
+        return t;
+    }
+};
+
+template<typename T>
+struct static_cast_helper<matrix<T,3,3>, math::quaternion<T> >
+{
+    static inline matrix<T,3,3> cast(math::quaternion<T> q)
+    {
+        return q.constructMatrix();
+    }
+};
+}
+
+}
+}
+
+#endif
diff --git a/src/nbl/builtin/CMakeLists.txt b/src/nbl/builtin/CMakeLists.txt
@@ -225,6 +225,7 @@ LIST_BUILTIN_RESOURCE(NBL_RESOURCES_TO_EMBED "hlsl/math/geometry.hlsl")
 LIST_BUILTIN_RESOURCE(NBL_RESOURCES_TO_EMBED "hlsl/math/intutil.hlsl")
 LIST_BUILTIN_RESOURCE(NBL_RESOURCES_TO_EMBED "hlsl/math/polar.hlsl")
 LIST_BUILTIN_RESOURCE(NBL_RESOURCES_TO_EMBED "hlsl/math/angle_adding.hlsl")
+LIST_BUILTIN_RESOURCE(NBL_RESOURCES_TO_EMBED "hlsl/math/quaternions.hlsl")
 LIST_BUILTIN_RESOURCE(NBL_RESOURCES_TO_EMBED "hlsl/math/equations/quadratic.hlsl")
 LIST_BUILTIN_RESOURCE(NBL_RESOURCES_TO_EMBED "hlsl/math/equations/cubic.hlsl")
 LIST_BUILTIN_RESOURCE(NBL_RESOURCES_TO_EMBED "hlsl/math/equations/quartic.hlsl")
