Adding upstream version 1.2.2.upstream/1.2.2upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 190 insertions, 0 deletions

diff --git a/src/transf_mat_3x4.cpp b/src/transf_mat_3x4.cpp
new file mode 100644
index 0000000..391783b
--- /dev/null
+++ b/src/transf_mat_3x4.cpp
@@ -0,0 +1,190 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * 3x4 transformation matrix to map points from projective 3-space into the projective plane
+ *
+ * Authors:
+ *   Maximilian Albert <Anhalter42@gmx.de>
+ *
+ * Copyright (C) 2007  Authors
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include "transf_mat_3x4.h"
+#include <2geom/affine.h>
+#include "svg/stringstream.h"
+#include "syseq.h"
+
+namespace Proj {
+
+TransfMat3x4::TransfMat3x4 () {
+    for (unsigned int i = 0; i < 3; ++i) {
+        for (unsigned int j = 0; j < 4; ++j) {
+            tmat[i][j] = (i == j ? 1 : 0); // or should we initialize all values with 0? does it matter at all?
+        }
+    }
+}
+
+TransfMat3x4::TransfMat3x4 (Proj::Pt2 vp_x, Proj::Pt2 vp_y, Proj::Pt2 vp_z, Proj::Pt2 origin) {
+    for (unsigned int i = 0; i < 3; ++i) {
+        tmat[i][0] = vp_x[i];
+        tmat[i][1] = vp_y[i];
+        tmat[i][2] = vp_z[i];
+        tmat[i][3] = origin[i];
+    }
+}
+
+TransfMat3x4::TransfMat3x4(TransfMat3x4 const &rhs) {
+    for (unsigned int i = 0; i < 3; ++i) {
+        for (unsigned int j = 0; j < 4; ++j) {
+            tmat[i][j] = rhs.tmat[i][j];
+        }
+    }
+}
+
+Pt2
+TransfMat3x4::column (Proj::Axis axis) const {
+    return Proj::Pt2 (tmat[0][axis], tmat[1][axis], tmat[2][axis]);
+}
+  
+Pt2
+TransfMat3x4::image (Pt3 const &point) {
+    double x = tmat[0][0] * point[0] + tmat[0][1] * point[1] + tmat[0][2] * point[2] + tmat[0][3] * point[3];
+    double y = tmat[1][0] * point[0] + tmat[1][1] * point[1] + tmat[1][2] * point[2] + tmat[1][3] * point[3];
+    double w = tmat[2][0] * point[0] + tmat[2][1] * point[1] + tmat[2][2] * point[2] + tmat[2][3] * point[3];
+
+    return Pt2 (x, y, w);
+}
+
+Pt3
+TransfMat3x4::preimage (Geom::Point const &pt, double coord, Proj::Axis axis) {
+    const double init_val = std::numeric_limits<double>::quiet_NaN();
+    double x[4] = { init_val, init_val, init_val, init_val };
+    double v[3] = { pt[Geom::X], pt[Geom::Y], 1.0 };
+    int index = (int) axis;
+
+    SysEq::SolutionKind sol = SysEq::gaussjord_solve<3,4>(tmat, x, v, index, coord, true);
+
+    if (sol != SysEq::unique) {
+        if (sol == SysEq::no_solution) {
+            g_print ("No solution. Please investigate.\n");
+        } else {
+            g_print ("Infinitely many solutions. Please investigate.\n");
+        }
+    }
+    return Pt3(x[0], x[1], x[2], x[3]);
+}
+ 
+void
+TransfMat3x4::set_image_pt (Proj::Axis axis, Proj::Pt2 const &pt) {
+    // FIXME: Do we need to adapt the coordinates in any way or can we just use them as they are?
+    for (int i = 0; i < 3; ++i) {
+        tmat[i][axis] = pt[i];
+    }
+}
+
+void
+TransfMat3x4::toggle_finite (Proj::Axis axis) {
+    g_return_if_fail (axis != Proj::W);
+    if (has_finite_image(axis)) {
+        Geom::Point dir (column(axis).affine());
+        Geom::Point origin (column(Proj::W).affine());
+        dir -= origin;
+        set_column (axis, Proj::Pt2(dir[Geom::X], dir[Geom::Y], 0));
+    } else {
+        Proj::Pt2 dir (column(axis));
+        Proj::Pt2 origin (column(Proj::W).affine());
+        dir = dir + origin;
+        dir[2] = 1.0;
+        set_column (axis, dir);
+    }
+}
+
+gchar *
+TransfMat3x4::pt_to_str (Proj::Axis axis) {
+    Inkscape::SVGOStringStream os;
+    os << tmat[0][axis] << " : "
+       << tmat[1][axis] << " : "
+       << tmat[2][axis];
+    return g_strdup(os.str().c_str());
+}
+
+/* Check for equality (with a small tolerance epsilon) */
+bool
+TransfMat3x4::operator==(const TransfMat3x4 &rhs) const
+{
+    // Should we allow a certain tolerance or "normalize" the matrices first?
+    for (int i = 0; i < 3; ++i) {
+        Proj::Pt2 pt1 = column(Proj::axes[i]);
+        Proj::Pt2 pt2 = rhs.column(Proj::axes[i]);
+        if (pt1 != pt2) {
+            return false;
+        }
+    }
+    return true;
+}
+
+/* Multiply a projective matrix by an affine matrix (by only multiplying the 'affine part' of the
+ * projective matrix) */
+TransfMat3x4
+TransfMat3x4::operator*(Geom::Affine const &A) const {
+    TransfMat3x4 ret;
+
+    for (int j = 0; j < 4; ++j) {
+        ret.tmat[0][j] = A[0]*tmat[0][j] + A[2]*tmat[1][j] + A[4]*tmat[2][j];
+        ret.tmat[1][j] = A[1]*tmat[0][j] + A[3]*tmat[1][j] + A[5]*tmat[2][j];
+        ret.tmat[2][j] = tmat[2][j];
+    }
+
+    return ret;
+}
+
+// FIXME: Shouldn't rather operator* call operator*= for efficiency? (Because in operator*=
+//        there is in principle no need to create a temporary object, which happens in the assignment)
+TransfMat3x4 &
+TransfMat3x4::operator*=(Geom::Affine const &A) {
+    *this = *this * A;
+    return *this;
+}
+
+void
+TransfMat3x4::copy_tmat(double rhs[3][4]) {
+    for (int i = 0; i < 3; ++i) {
+        for (int j = 0; j < 4; ++j) {
+            rhs[i][j] = tmat[i][j];
+        }
+    }
+}
+
+void
+TransfMat3x4::print () const {
+  g_print ("Transformation matrix:\n");
+  for (const auto & i : tmat) {
+    g_print ("  ");
+    for (double j : i) {
+      g_print ("%8.2f ", j);
+    }
+    g_print ("\n");
+  }
+}
+
+void
+TransfMat3x4::normalize_column (Proj::Axis axis) {
+    Proj::Pt2 new_col(column(axis));
+    new_col.normalize();
+    set_image_pt(axis, new_col);
+}
+
+
+} // namespace Proj
+
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :