/tags/rel-1-3-24/SWIG/Examples/GIFPlot/Guile/full/runme.scm

 1;;; Plot a 3D function
 2
 3;; Use the wrapped GIFPlot library
 4(use-modules (gifplot))
 5
 6;; Here is the function to plot
 7(define (func x y)
 8  (* 5
 9     (cos (* 2 (sqrt (+ (* x x) (* y y)))))
10     (exp (* -0.3 (sqrt (+ (* x x) (* y y)))))))
11
12;; Here are some plotting parameters
13(define xmin -5.0)
14(define xmax  5.0)
15(define ymin -5.0)
16(define ymax  5.0)
17(define zmin -5.0)
18(define zmax  5.0)
19
20;; Grid resolution
21(define nxpoints  60)
22(define nypoints  60)
23
24(define cmap (new-ColorMap "cmap"))
25(define frame (new-FrameBuffer 500 500))
26(FrameBuffer-clear frame (BLACK))
27
28(define p3 (new-Plot3D frame xmin ymin zmin xmax ymax zmax))
29(Plot3D-lookat p3 (* 2 (- zmax zmin)))
30(Plot3D-autoperspective p3 40)
31(Plot3D-rotu p3 60)
32(Plot3D-rotr p3 30)
33(Plot3D-rotd p3 10)
34
35(define (drawsolid)
36  (Plot3D-clear p3 (BLACK))
37  (Plot3D-start p3)
38  (let ((dx (/ (- xmax xmin) nxpoints))
39	(dy (/ (- ymax ymin) nypoints))
40	(cscale (/ 240 (- zmax zmin))))
41    (let x-loop ((x xmin) (i 0))
42      (cond
43       ((< i nxpoints)
44	(let y-loop ((y ymin) (j 0))
45	  (cond
46	   ((< j nypoints)
47	    (let* ((z1 (func x y))
48		   (z2 (func (+ x dx) y))
49		   (z3 (func (+ x dx) (+ y dy)))
50		   (z4 (func x (+ y dy)))
51		   (c1 (* cscale (- z1 zmin)))
52		   (c2 (* cscale (- z2 zmin)))
53		   (c3 (* cscale (- z3 zmin)))
54		   (c4 (* cscale (- z4 zmin)))
55		   (cc (/ (+ c1 c2 c3 c4) 4))
56		   (c  (round (max (min cc 239) 0))))
57	      (Plot3D-solidquad p3 x y z1 (+ x dx) y z2 (+ x dx) (+ y dy)
58				z3 x (+ y dy) z4 (+ c 16)))
59	    (y-loop (+ y dy) (+ j 1)))))
60	(x-loop (+ x dx) (+ i 1)))))))
61
62(display "Making a nice 3D plot...\n")
63(drawsolid)
64
65(FrameBuffer-writeGIF frame cmap "image.gif")
66(display "Wrote image.gif\n")