-// clip.cpp
-int clip_rect(double& x1, double& y1, double& x2, double& y2, const double rect[4]);
-int clip_segment(double& x1, double& y1, double& x2, double& y2, const double u, const double v);
-int clip_sector(double& x1, double& y1, double& x2, double& y2, const double u, const double v);
-int clip_circle(double& x1, double& y1, double& x2, double& y2, const double cx, const double cy, const double radius, double t1, double t2);
-int clip_triangle(double& x1, double& y1, double& x2, double& y2, const double u, const double v, const int clip_xaxis);
-
-// norm_ang.cpp
-double norm_ang (double theta);
-
-// xform.cpp
-void indent_mtx2(GRFMTX_2D m);
-void xlat_mtx2(GRFMTX_2D m, const double x, const double y);
-void scale_mtx2(GRFMTX_2D m, const double sx, const double sy);
-void rot_mtx2(GRFMTX_2D m, const double theta);
-void mult_mtx2(GRFMTX_2D m1, GRFMTX_2D m2, GRFMTX_2D result);
-void xform_mtx2(GRFMTX_2D m, double& x, double& y);
-void rotate2d(double x[], double y[], int pts, double angle);
-void xlat2d(double x[], double y[], int pts, double xoffset, double yoffset);
-void scale2d(double x[], double y[], int pts, double xfact, double yfact);
-
-// simpson.cpp
+// clip.cpp
+bool clip_rect (double& x1, double& y1, double& x2, double& y2, const double rect[4]);
+bool clip_segment (double& x1, double& y1, double& x2, double& y2, const double u, const double v);
+bool clip_sector (double& x1, double& y1, double& x2, double& y2, const double u, const double v);
+bool clip_circle (double& x1, double& y1, double& x2, double& y2, const double cx, const double cy, const double radius, double t1, double t2);
+bool clip_triangle (double& x1, double& y1, double& x2, double& y2, const double u, const double v, const int clip_xaxis);
+
+
+// xform.cpp
+void indent_mtx2 (GRFMTX_2D m);
+void xlat_mtx2 (GRFMTX_2D m, const double x, const double y);
+void scale_mtx2 (GRFMTX_2D m, const double sx, const double sy);
+void rot_mtx2 (GRFMTX_2D m, const double theta);
+void mult_mtx2 (const GRFMTX_2D m1, const GRFMTX_2D m2, GRFMTX_2D result);
+void xform_mtx2 (const GRFMTX_2D m, double& x, double& y);
+void copy_mtx2 (GRFMTX_2D to, const GRFMTX_2D from);
+void rotate2d (double x[], double y[], int pts, double angle);
+void xlat2d (double x[], double y[], int pts, double xoffset, double yoffset);
+void scale2d (double x[], double y[], int pts, double xfact, double yfact);
+
+// mathfuncs.cpp
+double normalizeAngle (double theta);