X-Git-Url: http://git.kpe.io/?a=blobdiff_plain;f=doc%2Fctsim-appendix.tex;h=a826258e35e415887b2a6c4046eee6a9de106a84;hb=ca7c001fce978b680543f8338a404b8c0701a935;hp=8657e9c664d9b40ef1506c01264eca1734016b2e;hpb=00c1e9f08a38db0e14d146fbadb2daa0faa30278;p=ctsim.git diff --git a/doc/ctsim-appendix.tex b/doc/ctsim-appendix.tex index 8657e9c..a826258 100644 --- a/doc/ctsim-appendix.tex +++ b/doc/ctsim-appendix.tex @@ -1,93 +1,125 @@ -\chapter{Appendix}\label{appendix}\index{Appendix}% -\setheader{{\it CHAPTER \thechapter}}{}{}{}{}{{\it CHAPTER \thechapter}}% -\setfooter{\thepage}{}{}{}{\manver}{\thepage}% +\appendix -\section{Simple Graphics Package}\index{Simple Graphics Package}% +\chapter{Simple Graphics Package}\label{appendix}\index{Simple Graphics Package} +\setheader{{\it Appendix \thechapter}}{}{}{\ctsimheadtitle}{}{{\it Appendix \thechapter}}% +\ctsimfooter% -\subsection{Overview}% Simple Graphics Package was created in 1980 by Kevin Rosenberg and -is modelled after the graphics library in Foley and van -Dam\cite{FOLEY82}. +is modelled after the hypothetical graphics library described by Foley and van +Dam\cite{FOLEY82}. It is designed to be platform-independent. -\begin{verbatim} - +------------------------+ - | World Coordinate level | - +-----------+------------+ - | - +-------------+-------------+ - | Clipping against Window() | - +-------------+-------------+ - | - +------------+-------------+ - | Convert to Normalized | - | device coordinates (NDC) | - +------------+-------------+ - | - +-------------+-------------+ - | Clipping against Viewport | - +-------------+-------------+ - | - +------------+-------------+ - | Convert to Physical | - | device coordinates (PDC) | - +--------------------------+ -\end{verbatim} +\section{Transformation Sequence} +\latexonly{ +\parbox{11cm}{ +\centerline{Master coordinate (MC) level} +\centerline{$\downarrow$} +\centerline{Apply \emph{Current transformation matrix}} +\centerline{$\downarrow$} +\centerline{World coordinate (WC) level} +\centerline{$\downarrow$} +\centerline{Clipping against Window} +\centerline{$\downarrow$} +\centerline{Convert to Normalized device coordinates (NDC)} +\centerline{$\downarrow$} +\centerline{Clipping against Viewport} +\centerline{$\downarrow$} +\centerline{Convert to Physical device coordinates (PDC)} +}} +\latexignore{ +\centerline{Master coordinate (MC) level} +\centerline{Apply \emph{Current transformation matrix}} +\centerline{World coordinate (WC) level} +\centerline{Clipping against Window} +\centerline{Convert to Normalized device coordinates (NDC)} +\centerline{Clipping against Viewport} +\centerline{Convert to Physical device coordinates (PDC)} +} -\subsection{Functions}% +\section{Functions}% -\subsubsection{World Coordinate Level} +\subsection{Master coordinate functions} \begin{twocollist} -\twocolitem{initgrf2}{Initialize 2 dimensional graphics} -\twocolitem{termgrf2}{Terminate 2 dimensional graphics} -\twocolitem{setColor(color)}{Set current drawing color} -\twocolitem{setLinestyle (style)}{Set current line style} -\twocolitem{setLinewidth (width)}{Set current line width} -\twocolitem{setTextColor (foreground, background)}{If back=-1, -then transparent} \twocolitem{setMarker (type, color)}{Set marker -attibutes} +\twocolitem{\texttt{setWindow(xmin,ymin,xmax,ymax)}}{Set window for world +coordinates} +\twocolitem{\texttt{moveAbs(x,y)}}{Move graphics cursor to absolute position} +\twocolitem{\texttt{moveRel(dx,dy)}}{Move graphics cursor relative to current position} +\twocolitem{\texttt{pointAbs(x,y)}}{Draw point at current position} +\twocolitem{\texttt{pointRel(dx,dy)}}{Draw point relative to current position} +\twocolitem{\texttt{lineAbs(x,y)}}{Draw line from current position to +absolute position} +\twocolitem{\texttt{lineRel(dx,dy)}}{Draw line from current position to position +relative to current position} +\twocolitem{\texttt{markerAbs(x,y)}}{Draw marker at current position} +\twocolitem{\texttt{markerRel(dx,dy)}}{Draw marker relative to current position} +\twocolitem{\texttt{polylineAbs(x[],y[],n)}}{Draw a series of lines to absolute position} +\twocolitem{\texttt{polylineRel(dx[],dy[],n)}}{Draw series of lines relative to current position} +\twocolitem{\texttt{drawString(str)}}{Draw text string at current positon} +\twocolitem{\texttt{drawCircle(r)}}{Draw circle at current positon} +\twocolitem{\texttt{drawArc(r,start,stop)}}{Draw arc with center at current positon} +\twocolitem{\texttt{drawRect(xmin,ymin,xmax,ymax)}}{Draw rectangle} \end{twocollist} -\subsubsection{State Commands} +\subsection{Normalized coordinate functions}% \begin{twocollist} -\twocolitem{Window(xmin, ymin, xmax, ymax)}{Set window for world -coordinates} \twocolitem{MoveAbs(x, y)}{Move graphics cursor} -\twocolitem{MoveRel(dx, dy)}{} \twocolitem{PointAbs (x, y)}{Plot -point at current position} \twocolitem{PointRel (dx, dy)}{} -\twocolitem{LineAbs2 (x, y)}{Draw line from current point to -point} \twocolitem{LineRel2 (dx, dy)}{} \twocolitem{MarkerAbs2 (x, -y)}{Draw marker at current position} \twocolitem{MarkerRel2 (dx, -dy)}{} \twocolitem{PolylineAbs (x[], y[], n)}{Draw a set of lines} -\twocolitem{PolylineRel (dx[], dy[], n)}{} -\twocolitem{wc\_to\_ndc(xwc, ywc, xndc, yndc)}{Convert from world -coord to NDC} \twocolitem{ndc\_to\_wc(xndc, yndc, xwc, -ywc)}{Convert from NDC to world coord} \twocolitem{DrawText -(str)}{Draw text string at current positon} +\twocolitem{\texttt{Viewport(xmin,ymin,xmax,ymax)}}{Viewport for window +in NDC} +\twocolitem{\texttt{stylus(x,y,beam)}}{Draw a line from current +position if beam = 1, otherwise move stylus to new position} +\twocolitem{\texttt{markerNDC(xndc,yndc)}}{Draw marker at NDC position} \end{twocollist} +\subsection{Master coordinate to World coordinate transformations}% +These transformation functions operate on the \emph{Current transformation +matrix} (CTM). -\subsubsection{Normalized Coordinate level}% \begin{twocollist} -\twocolitem{Viewport (xmin, ymin, xmax, ymax)}{Viewport for window -in NDC} \twocolitem{stylus (x, y, beam)}{Draw a line from current -position} \twocolitem{markerNDC(xndc, yndc)}{Draw marker at NDC -position} +\twocolitem{\texttt{clearCTM()}}{Sets the CTM to an identity matrix} +\twocolitem{\texttt{preTranslate(x,y)}}{Apply translation to CTM} +\twocolitem{\texttt{postTranslate(x,y)}}{Apply translation to CTM} +\twocolitem{\texttt{preScale(x,y)}}{Apply scale to CTM} +\twocolitem{\texttt{postScale(x,y)}}{Apply scale to CTM} +\twocolitem{\texttt{preRotate(angle)}}{Apply rotation to CTM} +\twocolitem{\texttt{postRotate(angle)}}{Apply rotation to CTM} +\twocolitem{\texttt{preShear(x,y)}}{Apply shear to CTM} +\twocolitem{\texttt{postShear(x,y)}}{Apply shear to CTM} \end{twocollist} +\subsection{Coordinate transformation functions}% +\begin{twocollist} +\twocolitem{\texttt{transformMCtoNDC(\&x,\&y)}}{Convert from master +coordinates to NDC} +\twocolitem{\texttt{transformNDCtoMC(\&x,\&y)}}{Convert from NDC to master +coordinates} +\end{twocollist} -\subsection{Coordinate Mapping} +\subsection{State functions} +\begin{twocollist} +\twocolitem{\texttt{eraseWindow()}}{Clears the screen} +\twocolitem{\texttt{setColor(color)}}{Set current pen color} +\twocolitem{\texttt{setLinestyle(style)}}{Set current pen style} +\twocolitem{\texttt{setLinewidth(width)}}{Set current pen width} +\twocolitem{\texttt{setTextColor(foreground, background)}}{Set text colors} +\twocolitem{\texttt{setMarker(type,color)}}{Set marker attibutes} +\twocolitem{\texttt{setRasterOp(rasterOp)}}{Set raster operator} +\end{twocollist} -\subsubsection{Mapping from world coordinates to physical device coordinates}% +\section{Coordinate Mapping} +\subsection{Dimensions} Window (World Coordinates): $X_{wmin}, X_{wmax}, Y_{wmin}, Y_{wmax}$ \\ Viewport (Normalized Device Coordinates): $X_{vmin}, X_{vmax}, Y_{vmin}, Y_{vmax}$\\ Physical (Physicial Device Coordinates): $X_{pmax}, Y_{pmax}$\\ +\subsection{Formulas} +To convert from Master coordinates to World coordinates: \\ +\centerline{Apply \emph{current transformation matrix}} + To convert from WC to NDC:\\ \begin{equation} - X_{ndc} = X_{vmin} + (X_{vmax} - X_{vmin}) (X_{wc} - X_{wmin}) / (X_{wmax} - X_{wmin}) +X_{ndc} = X_{vmin} + (X_{vmax} - X_{vmin}) (X_{wc} - X_{wmin}) / (X_{wmax} - X_{wmin}) \end{equation} \begin{equation} - Y_{ndc} = Y_{vmin} + (Y_{vmax} - Y_{vmin}) (Y_{wc} - Y_{wmin}) / (Y_{wmax} - Y_{wmin}) +Y_{ndc} = Y_{vmin} + (Y_{vmax} - Y_{vmin}) (Y_{wc} - Y_{wmin}) / (Y_{wmax} - Y_{wmin}) \end{equation} To convert from NDC to PDC: