new pstricks package pst-bezier (29jan09)

git-svn-id: svn://tug.org/texlive/trunk@12014 c570f23f-e606-0410-a88d-b1316a301751

1 files changed, 109 insertions, 0 deletions

diff --git a/Master/texmf-dist/dvips/pst-bezier/pst-bezier.pro b/Master/texmf-dist/dvips/pst-bezier/pst-bezier.pro
new file mode 100644
index 00000000000..560d027a807
--- /dev/null
+++ b/Master/texmf-dist/dvips/pst-bezier/pst-bezier.pro
@@ -0,0 +1,109 @@
+%% $Id: pst-bezier.pro 87 2009-01-29 10:37:06Z herbert $
+%% PostScript prologue for pstricks-add.tex.
+%%
+%% Version 0.01, 2009/01/29
+%%
+%% For distribution, see pst-bezier.tex.
+%%
+%% 
+tx@Dict begin
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% Auxiliary routines:
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% [x1 y1] [x2 y2] -> [ x1+y1  x2+y2 ]
+/AddArrays2d {
+    [ 3 1 roll %% Get the operands
+    2 copy
+    0 get exch
+    0 get add %% first component finished
+    %% second component:
+    3 1 roll
+    1 get exch
+    1 get add ]} bind def
+
+%% [x1 y1] [x2 y2] -> [ x1-x2  y1-y2 ]
+/SubArrays2d {
+    [ 3 1 roll exch
+    2 copy
+    0 get exch 0 get sub
+    3 1 roll
+    1 get exch
+    1 get sub ] } bind def
+
+%% [x y] s -> [s*x s*y]
+/ScaleArray2d {
+    [ 3 1 roll exch
+    2 copy
+    0 get mul
+    3 1 roll
+    1 get mul
+    ] } bind def
+
+
+%% << [Array of Bezier splines] /K 1 >> -> empty stack
+%% Thereby, a Bezier spline is described by an array:
+%% [x0 y0 x1 y1 x2 y2 x3 y3 sl sr]
+%% (x0,y0) is the right control point
+/pstBCurve {
+begin %% LaTeX provides the dictionary (see above comments)
+    1 1 Splines length 1 sub {
+        /K exch def % K is the index of the spline.
+%%
+	%% First control point:
+        Splines K get 0 get dup %% switch the cases /n and /s...
+	/n eq { %% `not specified' -> automatically computed
+            Splines K get 0 %% l(k) is going to be set...
+		%% | -> p(k-1)+(p(k)-p(k-2))*sl(k)
+                Splines K get 4 2 getinterval
+                Splines K 2 sub get 4 2 getinterval
+                SubArrays2d
+                Splines K get 6 get ScaleArray2d
+                Splines K 1 sub get 4 2 getinterval
+                AddArrays2d
+            putinterval %% ...setting l(k)
+        } if
+        /s eq { %% `symmetric' -> compute from r(k-1)
+            Splines K get 0 %% l(k):=
+		%% | -> 2*p(k-1)-r(k-1)
+                Splines K 1 sub get 4 2 getinterval 2 ScaleArray2d
+                Splines K 1 sub get 2 2 getinterval SubArrays2d
+            putinterval %%
+        } if
+
+	%% Second control point:
+        Splines K get 2 get dup %% (cases /n and /s)
+	/n eq { %% `not specified' -> automatically computed
+            Splines K get 2
+		%% | -> p(k)+(p(k+1)-p(k-1))*sr(k)
+                Splines K 1 sub get 4 2 getinterval
+                Splines K 1 add get 4 2 getinterval
+                SubArrays2d
+                Splines K get 7 get ScaleArray2d
+                Splines K get 4 2 getinterval
+                AddArrays2d
+            putinterval
+        } if
+        /s eq { %% `symmetric' -> compute from l(k+1)
+            Splines K get 2
+		%% | -> 2*p(k)-l(k+1)
+                Splines K get 4 2 getinterval 2 ScaleArray2d
+                Splines K 1 add get 0 2 getinterval SubArrays2d
+            putinterval
+        } if
+    } for %% all splines.
+    %%
+    %% The current point is already correctly set by the LaTeX macro.
+    %% So get ride of the 0th dummy spline.
+    Splines 1 Splines length 1 sub getinterval {%
+	aload pop pop pop %% get ride of the array itself and the scaling factor.
+       curveto% now the actual spline is on the stack...
+    } forall %% splines.
+    /Points [ %% now save the points for the showpoints-feature.
+        Splines 0 get 4 2 getinterval aload pop
+        Splines 1 Splines length 1 sub getinterval { aload pop pop pop } forall
+        ]
+    end def %% Put points in the top dictionary
+  } bind def
+end %% tx@Dict