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diff --git a/Master/texmf/doc/asymptote/examples/intro.asy b/Master/texmf/doc/asymptote/examples/intro.asy deleted file mode 100644 index fcafefb32a6..00000000000 --- a/Master/texmf/doc/asymptote/examples/intro.asy +++ /dev/null @@ -1,958 +0,0 @@ -orientation=Landscape; - -settings.tex="pdflatex"; - -import slide; -import three; -import animate; - -bool long=true; - -usepackage("mflogo"); - -usersetting(); - -viewportsize=pagewidth-2pagemargin; - -// To generate bibliographic references: -// asy -k goysr -// bibtex goysr_ -bibliographystyle("alpha"); - -itempen=fontsize(22pt); -defaultpen(itempen); -viewportmargin=(2,2); - -titlepage(long ? "Asymptote: The Vector Graphics Language" : - "Interactive TeX-Aware 3D Vector Graphics", - "John Bowman and Andy Hammerlindl", -"Department of Mathematical and Statistical Sciences\\ - University of Alberta\\ -%and Instituto Nacional de Matem\'atica Pura e Aplicada (IMPA) -\medskip\Green{Collaborators: Orest Shardt, Michail Vidiassov}", -"June 30, 2010", -"http://asymptote.sf.net/intro.pdf"); - -title("History"); -item("1979: \TeX\ and \MF\ (Knuth)"); -item("1986: 2D B\'ezier control point selection (Hobby)"); -item("1989: MetaPost (Hobby)"); -item("2004: Asymptote"); -subitem("2004: initial public release (Hammerlindl, Bowman, \& Prince)"); -subitem("2005: 3D B\'ezier control point selection (Bowman)"); -subitem("2008: 3D interactive \TeX\ within PDF files (Shardt \& Bowman)"); -subitem("2009: 3D billboard labels that always face camera (Bowman)"); -subitem("2010: 3D PDF enhancements (Vidiassov \& Bowman)"); - -title("Statistics (as of June, 2010)"); -item("Runs under Linux/UNIX, Mac OS X, Microsoft Windows."); -item("4000 downloads/month from primary\hfill\\ - {\tt asymptote.sourceforge.net} site alone."); -item("80\ 000 lines of low-level C++ code."); -item("36\ 000 lines of high-level Asymptote code."); - -if(long) { -title("Vector Graphics"); -item("Raster graphics assign colors to a grid of pixels."); -figure("pixel.pdf"); -item("Vector graphics are graphics which still maintain their look when - inspected at arbitrarily small scales."); -asyfigure(asywrite(" -picture pic; - -path zoombox(real h) { - return box((-h,-h/2),(min(10,h),min(10,h)/2)); -} - -frame zoom(real h, real next=0) { - frame f; - draw(f, (0,-100){W}..{E}(0,0), Arrow); - clip(f, zoombox(h)); - if(next > 0) - draw(f, zoombox(next)); - - return scale(100/h)*f; -} - -add(zoom(100), (0,0)); -add(zoom(10), (200,0)); -add(zoom(1), (400,0)); -")); -} - -title("Cartesian Coordinates"); - -item("Asymptote's graphical capabilities are based on four primitive - commands: {\tt draw}, {\tt label}, {\tt fill}, {\tt clip} \cite{Bowman08}"); - -asyfilecode("diagonal"); -item("units are {\tt PostScript} {\it big points\/} (1 {\tt bp} = -1/72 {\tt inch})"); -item("{\tt --} means join the points with a linear segment to create -a {\it path}"); - -item("{\it cyclic\/} path:"); - -asycode(" -draw((0,0)--(100,0)--(100,100)--(0,100)--cycle); -"); - -title("Scaling to a Given Size"); - -item("{\tt PostScript} units are often inconvenient."); - -item("Instead, scale user coordinates to a specified final size:"); - -asyfilecode("square"); - -item("One can also specify the size in {\tt cm}:"); - -asycode(" -size(3cm,3cm); -draw(unitsquare); -"); - -title("Labels"); - -item("Adding and aligning \LaTeX\ labels is easy:"); - -asycode(preamble="defaultpen(fontsize("+string(fontsize(itempen))+"));", -"size(6cm); -draw(unitsquare); -label(\"$A$\",(0,0),SW); -label(\"$B$\",(1,0),SE); -label(\"$C$\",(1,1),NE); -label(\"$D$\",(0,1),NW); -"); - -title("2D B\'ezier Splines"); - -item("Using {\tt ..} instead of {\tt --} specifies a {\it B\'ezier cubic -spline}:"); - -code(" -draw(z0 .. controls c0 and c1 .. z1,blue); -"); -asyfigure(asywrite("defaultpen(fontsize("+string(fontsize(itempen))+")); -size(0,7cm); -pair z0=(0,0); -pair c0=(1,1); -pair c1=(2,1); -pair z1=(3,0); -draw(z0..controls c0 and c1 .. z1,blue); -draw(z0--c0--c1--z1,dashed); -dot(\"$z_0$\",z0,W,red); -dot(\"$c_0$\",c0,NW,red); -dot(\"$c_1$\",c1,NE,red); -dot(\"$z_1$\",z1,red); -")); - -equation("(1-t)^3 z_0+3t(1-t)^2 c_0+3t^2(1-t) c_1+t^3 z_1, \qquad t\in [0,1]."); - -title("Smooth Paths"); - -item("Asymptote can choose control points for you, using the algorithms of -Hobby and Knuth \cite{Hobby86,Knuth86b}:"); - -string bean=" -pair[] z={(0,0), (0,1), (2,1), (2,0), (1,0)}; -"; - -asycode(preamble="size(130,0);",bean+" -draw(z[0]..z[1]..z[2]..z[3]..z[4]..cycle, - grey+linewidth(5)); -dot(z,linewidth(7)); -"); - -item("First, linear equations involving the curvature are solved to find the - direction through each knot. Then, control points along those directions - are chosen:"); - -asyfigure(asywrite(preamble="size(130,0);",bean+" -path p=z[0]..z[1]..z[2]..z[3]..z[4]..cycle; - -dot(z); -draw(p,lightgrey+linewidth(5)); -dot(z); - -picture output; -save(); -for(int i=0; i<length(p); ++i) { - pair z=point(p,i), dir=dir(p,i); - draw((z-0.3dir)--(z+0.3dir), Arrow); -} -add(output, currentpicture.fit(), (-0.5inch, 0), W); -restore(); - -save(); -guide g; -for(int i=0; i<length(p); ++i) { - dot(precontrol(p,i)); - dot(postcontrol(p,i)); - g=g--precontrol(p,i)--point(p,i)--postcontrol(p,i); -} -draw(g--cycle,dashed); -add(output, currentpicture.fit(), (+0.5inch, 0), E); -restore(); - -shipout(output); -")); - -title("Filling"); -item("The {\tt fill} primitive to fill the inside of a path:"); -asycode(preamble="size(0,200);"," -path star; -for(int i=0; i < 5; ++i) - star=star--dir(90+144i); -star=star--cycle; - -fill(star,orange+zerowinding); -draw(star,linewidth(3)); - -fill(shift(2,0)*star,blue+evenodd); -draw(shift(2,0)*star,linewidth(3)); -"); - -title("Filling"); -item("Use a list of paths to fill a region with holes:"); -asycode(preamble="size(0,300);"," -path[] p={scale(2)*unitcircle, reverse(unitcircle)}; -fill(p,green+zerowinding); -"); - -title("Clipping"); -item("Pictures can be clipped to a path:"); -asycode(preamble=" -size(0,200); -guide star; -for(int i=0; i<5; ++i) - star=star--dir(90+144i); -star=star--cycle;"," -fill(star,orange+zerowinding); -clip(scale(0.7)*unitcircle); -draw(scale(0.7)*unitcircle); -"); - -title("Affine Transforms"); - -item("Affine transformations: shifts, rotations, reflections, and scalings - can be applied to pairs, paths, pens, strings, and even whole pictures:"); - -code(" -fill(P,blue); -fill(shift(2,0)*reflect((0,0),(0,1))*P, red); -fill(shift(4,0)*rotate(30)*P, yellow); -fill(shift(6,0)*yscale(0.7)*xscale(2)*P, green); -"); -asyfigure(asywrite(" -size(500,0); -real bw=0.15; -real sw=0.2; -real r=0.15; - -path outside=(0,0)--(0,1)-- - (bw+sw,1)..(bw+sw+r+bw,1-(r+bw))..(bw+sw,1-2(r+bw))-- - (bw,1-2(r+bw))--(bw,0)--cycle; -path inside=(bw,1-bw-2r)--(bw,1-bw)-- - (bw+sw,1-bw)..(bw+sw+r,1-bw-r)..(bw+sw,1-bw-2r)--cycle; -//fill(new path[] {outside, reverse(inside)},yellow); - -path[] P={outside, reverse(inside)}; - -fill(P,blue); -fill(shift(2,0)*reflect((0,0),(0,1))*P, red); -fill(shift(4,0)*rotate(30)*P, yellow); -fill(shift(6,0)*yscale(0.7)*xscale(2)*P, green); -")); - -if(long) { -title("C++/Java-like Programming Syntax"); - -code("// Declaration: Declare x to be real: -real x; - -// Assignment: Assign x the value 1. -x=1.0; - -// Conditional: Test if x equals 1 or not. -if(x == 1.0) { - write(\"x equals 1.0\"); -} else { - write(\"x is not equal to 1.0\"); -} - -// Loop: iterate 10 times -for(int i=0; i < 10; ++i) { - write(i); -}"); -} - -title("Modules"); - -item("There are modules for Feynman diagrams,"); -asyfigure("eetomumu","height=6cm"); -remark("data structures,"); -asyfigure(asywrite(" -import binarytree; - -binarytree bt=binarytree(1,2,4,nil,5,nil,nil,0,nil,nil,3,6,nil,nil,7); -draw(bt); -"),"height=6cm"); -newslide(); -remark("algebraic knot theory:"); -asyfigure("knots"); -equations("\Phi\Phi(x_1,x_2,x_3,x_4,x_5) - = &\rho_{4b}(x_1+x_4,x_2,x_3,x_5) + \rho_{4b}(x_1,x_2,x_3,x_4) \\ - + &\rho_{4a}(x_1,x_2+x_3,x_4,x_5) - \rho_{4b}(x_1,x_2,x_3,x_4+x_5) \\ - - &\rho_{4a}(x_1+x_2,x_3,x_4,x_5) - \rho_{4a}(x_1,x_2,x_4,x_5)."); - -if(long) { -title("Textbook Graph"); -asy(nativeformat(),"exp"); -filecode("exp.asy"); -label(graphic("exp."+nativeformat(),"height=10cm"),(0.5,0), - Fill(figureborder,figuremattpen)); - -title("Scientific Graph"); -asyfilecode("lineargraph","height=13cm",newslide=true); - -title("Data Graph"); -asyfilecode("datagraph","height=13cm",newslide=true); - -title("Imported Data Graph"); -asyfilecode("filegraph","height=15cm",newslide=true); - -title("Logarithmic Graph"); -asyfilecode("loggraph","height=15cm",newslide=true); -title("Secondary Axis"); -} else -title("Scientific Graph"); - -asyfigure("secondaryaxis","height=15cm"); - -title("Images and Contours"); -asyfigure("imagecontour","height=17cm"); - -title("Multiple Graphs"); -asyfigure("diatom","height=17cm"); - -title("Hobby's 2D Direction Algorithm"); -item("A tridiagonal system of linear equations is solved to determine any unspecified directions $\phi_k$ and $\theta_k$ through each knot $z_k$:"); - -equation("\frac{\theta_{k-1}-2\phi_k}{\ell_k}= -\frac{\phi_{k+1}-2\theta_k}{\ell_{k+1}}."); - -asyfigure("Hobbydir","height=9cm"); - -item("The resulting shape may be adjusted by modifying optional {\it tension\/} parameters and {\it curl\/} boundary conditions."); - -title("Hobby's 2D Control Point Algorithm"); -item("Having prescribed outgoing and incoming path directions $e^{i\theta}$ -at node~$z_0$ and $e^{i\phi}$ at node $z_1$ relative to the -vector $z_1-z_0$, the control points are determined as:"); - -equations("u&=&z_0+e^{i\theta}(z_1-z_0)f(\theta,-\phi),\nonumber\\ -v&=&z_1-e^{i\phi}(z_1-z_0)f(-\phi,\theta),"); - -remark("where the relative distance function $f(\theta,\phi)$ is given by Hobby [1986]."); - -asyfigure("Hobbycontrol","height=9cm"); - -if(long) { -title("B\'ezier Curves in 3D"); - -item("Apply an affine transformation"); - -equation("x'_i=A_{ij} x_j+C_i"); - -remark("to a B\'ezier curve:"); - -equation("\displaystyle x(t)=\sum_{k=0}^3 B_k(t) P_k, \qquad t\in [0,1]."); - -item("The resulting curve is also a B\'ezier curve:"); - -skip(-2); - -equations("x'_i(t)&=&\sum_{k=0}^3 B_k(t) A_{ij}(P_k)_j+C_i\nonumber\\ -&=&\sum_{k=0}^3 B_k(t) P'_k,"); - -skip(-2); - -remark("where $P'_k$ is the transformed $k^{\rm th}$ control point, noting -$\displaystyle\sum_{k=0}^3 B_k(t)=1.$"); -} - -title("3D Generalization of Direction Algorithm"); - -item("Must reduce to 2D algorithm in planar case."); - -item("Determine directions by applying Hobby's algorithm in the plane containing $z_{k-1}$, $z_k$, $z_{k+1}$."); - -// Reformulate Hobby's equations in terms of the angle $\psi_k=$ -item("The only ambiguity that can arise is the overall sign of the angles, which relates to viewing each 2D plane from opposing normal directions."); - -item("A reference vector based on the mean unit normal of successive segments can be used to resolve such ambiguities \cite{Bowman07,Bowman09}"); - -title("3D Control Point Algorithm"); - -item("Express Hobby's algorithm in terms of the absolute directions $\omega_0$ and~$\omega_1$:"); -skip(-1); -equation("u=z_0+\omega_0\left|z_1-z_0\right|f(\theta,-\phi),"); -equation("v=z_1-\omega_1\left|z_1-z_0\right|f(-\phi,\theta),"); - -asyfigure("Hobbycontrol"); - -remark("interpreting $\theta$ and $\phi$ as the angle between the corresponding path direction vector and $z_1-z_0$."); - -item("Here there is an unambiguous reference vector for determining the relative sign of the angles $\phi$ and $\theta$."); - -viewportmargin=(2,0.5cm); -//defaultpen(1.0); -title("Interactive 3D Saddle"); -item("A unit circle in the $X$--$Y$ plane may be constructed with: -{\tt (1,0,0)..(0,1,0)..(-1,0,0)..(0,-1,0)..cycle}:"); -asyinclude("unitcircle3",8cm); -remark("and then distorted into the saddle\\ -{\tt (1,0,0)..(0,1,1)..(-1,0,0)..(0,-1,1)..cycle}:"); -asyinclude("saddle",8cm); -//defaultpen(0.5); - -title("Lifting TeX to 3D"); -item("Glyphs are first split into simply connected regions and then decomposed into planar B\'ezier surface patches \cite{Bowman09,Shardt10}:"); -asyfigure("../examples/partitionExample"); - -viewportmargin=(2,1cm); -title("Label Manipulation"); -item("They can then be extruded and/or arbitrarily transformed:"); -asyinclude("../examples/label3solid"); - -title("Billboard Labels"); -defaultpen(fontsize(36pt)); -asyinclude("../examples/billboard",15cm); -defaultpen(itempen); - -title("Smooth 3D surfaces"); -asyinclude("../examples/sinc",25cm); - -title("Curved 3D Arrows"); -asyinclude("../examples/arrows3",20cm); - -title("Slide Presentations"); -item("Asymptote has a module for preparing slides."); -item("It even supports embedded high-resolution PDF movies."); - -code(' -title("Slide Presentations"); -item("Asymptote has a module for preparing slides."); -item("It even supports embedded high-resolution PDF movies."); -'); -remark("\quad\ldots"); - -import graph; - -pen p=linewidth(1); -pen dotpen=linewidth(5); - -pair wheelpoint(real t) {return (t+cos(t),-sin(t));} - -guide wheel(guide g=nullpath, real a, real b, int n) -{ - real width=(b-a)/n; - for(int i=0; i <= n; ++i) { - real t=a+width*i; - g=g--wheelpoint(t); - } - return g; -} - -real t1=0; -real t2=t1+2*pi; - -picture base; -draw(base,circle((0,0),1),p); -draw(base,wheel(t1,t2,100),p+linetype("0 2")); -yequals(base,Label("$y=-1$",1.0),-1,extend=true,p+linetype("4 4")); -xaxis(base,Label("$x$",align=3SW),0,p); -yaxis(base,"$y$",0,1.3,p); -pair z1=wheelpoint(t1); -pair z2=wheelpoint(t2); -dot(base,z1,dotpen); -dot(base,z2,dotpen); - -animation a; - -int n=25; -real dt=(t2-t1)/n; -for(int i=0; i <= n; ++i) { - picture pic; - size(pic,24cm); - real t=t1+dt*i; - add(pic,base); - draw(pic,circle((t,0),1),p+red); - dot(pic,wheelpoint(t),dotpen); - a.add(pic); -} - -display(a.pdf(delay=150,"controls")); - -title("Automatic Sizing"); -item("Figures can be specified in user coordinates, then - automatically scaled to the desired final size."); -asyfigure(asywrite(" -import graph; - -size(0,100); - -frame cardsize(real w=0, real h=0, bool keepAspect=Aspect) { - picture pic; - pic.size(w,h,keepAspect); - - real f(real t) {return 1+cos(t);} - - guide g=polargraph(f,0,2pi,operator ..)--cycle; - filldraw(pic,g,pink); - - xaxis(pic,\"$x$\",above=true); - yaxis(pic,\"$y$\",above=true); - - dot(pic,\"$(a,0)$\",(1,0),N); - dot(pic,\"$(2a,0)$\",(2,0),N+E); - - frame f=pic.fit(); - label(f,\"{\tt size(\"+string(w)+\",\"+string(h)+\");}\",point(f,S),align=S); - return f; -} - -add(cardsize(0,50), (0,0)); -add(cardsize(0,100), (230,0)); -add(cardsize(0,200), (540,0)); -")); - -title("Deferred Drawing"); -item("We can't draw a graphical object until we know the scaling - factors for the user coordinates."); -item("Instead, store a function that, given the scaling information, draws - the scaled object."); -code(" -void draw(picture pic=currentpicture, path g, pen p=currentpen) { - pic.add(new void(frame f, transform t) { - draw(f,t*g,p); - }); - pic.addPoint(min(g),min(p)); - pic.addPoint(max(g),max(p)); -} -"); - -title("Coordinates"); -item("Store bounding box information as the sum of user and true-size - coordinates:"); -asyfigure(asywrite(" -size(0,150); - -path q=(0,0){dir(70)}..{dir(70)}(100,50); -pen p=rotate(30)*yscale(0.7)*(lightblue+linewidth(20)); -draw(q,p); -draw((90,10),p); - -currentpicture.add(new void(frame f, transform t) { - draw(f,box(min(t*q)+min(p),max(t*q)+max(p)), dashed); - }); - -draw(box(min(q),max(q))); - -frame f; -draw(f,box(min(p),max(p))); - -add(f,min(q)); -add(f,max(q)); - -draw(q); -")); - -code("pic.addPoint(min(g),min(p)); -pic.addPoint(max(g),max(p));"); -item("Filling ignores the pen width:"); -code("pic.addPoint(min(g),(0,0)); -pic.addPoint(max(g),(0,0));"); -item("Communicate with \LaTeX\ {\it via\/} a pipe to determine label sizes:"); - -asyfigure(asywrite(" -size(0,100); - -pen p=fontsize(30pt); -frame f; -label(f, \"$E=mc^2$\", p); -draw(f, box(min(f),max(f))); -shipout(f); -")); - -title("Sizing"); - -item("When scaling the final figure to a given size $S$, we first need to - determine a scaling factor $a>0$ and a shift $b$ so that all of the - coordinates when transformed will lie in the interval $[0,S]$."); - -item("That is, if $u$ and $t$ are the user and truesize components:"); -equation("0\le au+t+b \le S."); - -item("Maximize the variable $a$ subject to a number of inequalities."); - -item("Use the simplex method to solve the resulting linear programming problem."); - -if(long) { -title("Sizing"); -item("Every addition of a coordinate $(t,u)$ adds two restrictions"); -equation("au+t+b\ge 0,"); -equation("au+t+b\le S,"); -remark("and each drawing component adds two coordinates."); -item("A figure could easily produce thousands of restrictions, making the - simplex method impractical."); - -item("Most of these restrictions are redundant, however. For instance, with - concentric circles, only the largest circle needs to be accounted for."); -asyfigure(asywrite(" -import palette; -size(160,0); -pen[] p=Rainbow(NColors=11); -for(int i=1; i<10; ++i) { - draw(scale(i)*unitcircle, p[i]+linewidth(2)); -} -")); - -title("Redundant Restrictions"); -item("In general, if $u\le u'$ and $t\le t'$ then"); -equation("au+t+b\le au'+t'+b"); -remark("for all choices of $a>0$ and $b$, so"); -equation("0\le au+t+b\le au'+t'+b\le S."); -item("This defines a partial ordering on coordinates. When sizing a picture, - the program first computes which coordinates are maximal (or minimal) and - only sends effective constraints to the simplex algorithm."); -item("In practice, the linear programming problem will have less than a dozen - restraints."); -item("All picture sizing is implemented in Asymptote code."); -} - -title("Infinite Lines"); -item("Deferred drawing allows us to draw infinite lines."); -code("drawline(P, Q);"); - -asyfigure("elliptic","height=12cm"); - -title("Helpful Math Notation"); - -item("Integer division returns a {\tt real}. Use {\tt quotient} for an integer - result:"); -code("3/4 == 0.75 quotient(3,4) == 0"); - -item("Caret for real and integer exponentiation:"); -code("2^3 2.7^3 2.7^3.2"); - -item("Many expressions can be implicitly scaled by a numeric constant:"); -code("2pi 10cm 2x^2 3sin(x) 2(a+b)"); - -item("Pairs are complex numbers:"); -code("(0,1)*(0,1) == (-1,0)"); - -title("Function Calls"); - -item("Functions can take default arguments in any position. Arguments are - matched to the first possible location:"); -string unitsize="unitsize(0.65cm);"; -string preamble="void drawEllipse(real xsize=1, real ysize=xsize, pen p=blue) { - draw(xscale(xsize)*yscale(ysize)*unitcircle, p); -} -"; - -asycode(preamble=unitsize,preamble+" -drawEllipse(2); -drawEllipse(red); -"); - -item("Arguments can be given by name:"); -asycode(preamble=unitsize+preamble," -drawEllipse(xsize=2, ysize=1); -drawEllipse(ysize=2, xsize=3, green); -"); - -if(long) { -title("Rest Arguments"); -item("Rest arguments allow one to write a function that takes an arbitrary - number of arguments:"); -code(" -int sum(... int[] nums) { - int total=0; - for(int i=0; i < nums.length; ++i) - total += nums[i]; - return total; -} - -sum(1,2,3,4); // returns 10 -sum(); // returns 0 -sum(1,2,3 ... new int[] {4,5,6}); // returns 21 - -int subtract(int start ... int[] subs) { - return start - sum(... subs); -} -"); -} - -title("High-Order Functions"); - -item("Functions are first-class values. They can be passed to other - functions:"); -code("import graph; -real f(real x) { - return x*sin(10x); -} -draw(graph(f,-3,3,300),red);"); -asyfigure(asywrite(" -import graph; -size(300,0); -real f(real x) { - return x*sin(10x); -} -draw(graph(f,-3,3,300),red); -")); - -if(long) { -title("Higher-Order Functions"); -item("Functions can return functions:"); -equation("f_n(x)=n\sin\left(\frac{x}{n}\right)."); -skip(); -string preamble=" -import graph; -size(300,0); -"; -string graphfunc2=" -typedef real func(real); -func f(int n) { - real fn(real x) { - return n*sin(x/n); - } - return fn; -} - -func f1=f(1); -real y=f1(pi); - -for(int i=1; i<=5; ++i) - draw(graph(f(i),-10,10),red); -"; -code(graphfunc2); -string name=asywrite(graphfunc2,preamble=preamble); -asy(nativeformat(),name+".asy"); -label(graphic(name+"."+nativeformat()),(0.5,0), - Fill(figureborder,figuremattpen)); - -title("Anonymous Functions"); - -item("Create new functions with {\tt new}:"); -code(" -path p=graph(new real (real x) { return x*sin(10x); },-3,3,red); - -func f(int n) { - return new real (real x) { return n*sin(x/n); }; -}"); - -item("Function definitions are just syntactic sugar for assigning function -objects to variables."); -code(" -real square(real x) { - return x^2; -} -"); - -remark("is equivalent to"); -code(" -real square(real x); -square=new real (real x) { - return x^2; -}; -"); - -title("Structures"); - -item("As in other languages, structures group together data."); -code(" -struct Person { - string firstname, lastname; - int age; -} -Person bob=new Person; -bob.firstname=\"Bob\"; -bob.lastname=\"Chesterton\"; -bob.age=24; -"); - -item("Any code in the structure body will be executed every time a new structure - is allocated..."); -code(" -struct Person { - write(\"Making a person.\"); - string firstname, lastname; - int age=18; -} -Person eve=new Person; // Writes \"Making a person.\" -write(eve.age); // Writes 18. -"); - -title("Modules"); - -item("Function and structure definitions can be grouped into modules:"); -code(" -// powers.asy -real square(real x) { return x^2; } -real cube(real x) { return x^3; } -"); -remark("and imported:"); -code(" -import powers; -real eight=cube(2.0); -draw(graph(powers.square, -1, 1)); -"); -} - -title("Object-Oriented Programming"); -item("Functions are defined for each instance of a structure."); -code(" -struct Quadratic { - real a,b,c; - real discriminant() { - return b^2-4*a*c; - } - real eval(real x) { - return a*x^2 + b*x + c; - } -} -"); - -item("This allows us to construct ``methods'' which are just normal functions - declared in the environment of a particular object:"); -code(" -Quadratic poly=new Quadratic; -poly.a=-1; poly.b=1; poly.c=2; - -real f(real x)=poly.eval; -real y=f(2); -draw(graph(poly.eval, -5, 5)); -"); - -title("Specialization"); - -item("Can create specialized objects just by redefining methods:"); -code(" -struct Shape { - void draw(); - real area(); -} - -Shape rectangle(real w, real h) { - Shape s=new Shape; - s.draw = new void () { - fill((0,0)--(w,0)--(w,h)--(0,h)--cycle); }; - s.area = new real () { return w*h; }; - return s; -} - -Shape circle(real radius) { - Shape s=new Shape; - s.draw = new void () { fill(scale(radius)*unitcircle); }; - s.area = new real () { return pi*radius^2; } - return s; -} -"); - -title("Overloading"); -item("Consider the code:"); -code(" -int x1=2; -int x2() { - return 7; -} -int x3(int y) { - return 2y; -} - -write(x1+x2()); // Writes 9. -write(x3(x1)+x2()); // Writes 11. -"); - -title("Overloading"); -item("{\tt x1}, {\tt x2}, and {\tt x3} are never used in the same context, so - they can all be renamed {\tt x} without ambiguity:"); -code(" -int x=2; -int x() { - return 7; -} -int x(int y) { - return 2y; -} - -write(x+x()); // Writes 9. -write(x(x)+x()); // Writes 11. -"); - -item("Function definitions are just variable definitions, but variables are - distinguished by their signatures to allow overloading."); - -title("Operators"); -item("Operators are just syntactic sugar for functions, and can be addressed or - defined as functions with the {\tt operator} keyword."); -code(" -int add(int x, int y)=operator +; -write(add(2,3)); // Writes 5. - -// Don't try this at home. -int operator +(int x, int y) { - return add(2x,y); -} -write(2+3); // Writes 7. -"); -item("This allows operators to be defined for new types."); - -title("Operators"); -item("Operators for constructing paths are also functions:"); -code("a.. controls b and c .. d--e"); -remark("is equivalent to"); -code( - "operator --(operator ..(a, operator controls(b,c), d), e)"); -item("This allowed us to redefine all of the path operators for 3D paths."); - -title("Summary"); - -item("Asymptote:"); -subitem("uses IEEE floating point numerics;"); -subitem("uses C++/Java-like syntax;"); -subitem("supports deferred drawing for automatic picture sizing;"); -subitem("supports Grayscale, RGB, CMYK, and HSV colour spaces;"); -subitem("supports PostScript shading, pattern fills, and function shading;"); -subitem("can fill nonsimply connected regions;"); -subitem("generalizes MetaPost path construction algorithms to 3D;"); -subitem("lifts \TeX\ to 3D;"); -subitem("supports 3D billboard labels and PDF grouping."); - -bibliography("refs"); - -viewportmargin=(2,2); -viewportsize=0; -defaultpen(0.5); -title("\mbox{Asymptote: 2D \& 3D Vector Graphics Language}"); -asyinclude("../examples/logo3"); -skip(); -center("\tt http://asymptote.sf.net"); -center("(freely available under the LGPL license)"); - -// LocalWords: pdflatex mflogo viewportsize pagewidth pagemargin goysr bibtex -// LocalWords: itempen defaultrender medskip Orest Shardt Vidiassov MF ezier -// LocalWords: Hammerlindl MetaPost PDF hfill LGPL pdf asywrite zoombox LaTeX -// LocalWords: asyfilecode PostScript asycode unitsquare beziercurve grey bw -// LocalWords: lightgrey zerowinding evenodd sw unitsize drawEllipse nums fn -// LocalWords: frac graphfunc func nativeformat figureborder figuremattpen bt -// LocalWords: firstname lastname eval eetomumu binarytree filecode datagraph -// LocalWords: lineargraph filegraph loggraph secondaryaxis imagecontour ij -// LocalWords: tridiagonal Hobbydir nonumber Hobbycontrol th viewportmargin -// LocalWords: asyinclude dotpen wheelpoint yequals xaxis yaxis cardsize mc -// LocalWords: polargraph filldraw addPoint lightblue truesize le au NColors -// LocalWords: drawline unityroot mult oct intang IEEE numerics HSV colour -// LocalWords: nonsimply |