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| author | scuri <scuri> | 2008-10-17 06:10:33 +0000 |
|---|---|---|
| committer | scuri <scuri> | 2008-10-17 06:10:33 +0000 |
| commit | 7b52cc13af4e85f1ca2deb6b6c77de9c95ea0dcf (patch) | |
| tree | d0857278bde2eff784227c57dcaf930346ceb7ac /html/en/drv/cgm.html | |
First commit - moving from LuaForge to SourceForge
Diffstat (limited to 'html/en/drv/cgm.html')
| -rw-r--r-- | html/en/drv/cgm.html | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/html/en/drv/cgm.html b/html/en/drv/cgm.html new file mode 100644 index 0000000..17ca141 --- /dev/null +++ b/html/en/drv/cgm.html @@ -0,0 +1,184 @@ +<!doctype HTML PUBLIC "-//IETF//DTD HTML//EN"> +<html> + +<head> +<meta http-equiv="Content-Language" content="en-us"> +<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> +<title>CD_CGM</title> +<link rel="stylesheet" type="text/css" href="../../style.css"> +</head> + +<body> + +<h2>CD_CGM - <em>Computer Graphics Metafile Driver </em>(cdcgm.h)</h2> + + <p>This driver allows generating a Computer Graphics Metafile, which is an ANSI standard for the persistent storage of + graphics primitives. The file usually has an extension .CGM.</p> + +<h3>Use</h3> + + <p>The file file is created by means of a call to the function <font face="Courier"> + <a href="../func/init.html#cdCreateCanvas"><strong>cdCreateCanvas</strong></a>(CD_CGM, + Data)</font>, which <b>opens</b> the file and writes its header. Then, other functions in the CD library can be called + as usual. The <font face="Courier">Data</font> parameter string has the following format:</p> + + <pre><em>"filename [widthxheight] [resolution] [-t] -p[precision]" or in C style "<strong><tt>%s %gx%g %g %s</tt></strong>"</em></pre> + + <p>Only the parameter <font face="Courier">filename</font> is required. The filename must be inside double quotes (") + if it has spaces.<font face="Courier"> Width</font> and <font face="Courier">height</font> are provided in millimeters + (note the lowercase "x" between them), and their default value in pixels is <font face="Courier">INT_MAX</font> for + both dimensions. When the canvas' size is not specified, the VDC Extension saved to the file is the image's bounding + rectangle. The resolution is the number of pixels per millimeter; its default value is "3.78 pixels/mm" (96 DPI). + <font face="Courier">Width</font>, <font face="Courier">height</font> and <font face="Courier">resolution</font> are + real values. <font face="Courier">Width</font>, <font face="Courier">height</font> and <font face="Courier">resolution</font> + are used only by <strong><font face="Courier">cdGetCanvasSize</font> </strong>and in pixel-millimeter conversion. + Parameter <font face="Courier">-t</font> modifies the codification. Parameter <font face="Courier">-p</font> specifies + the precision of integers, which can be 16 (default) or 32.</p> + <p>Any amount of such canvases may exist simultaneously. It is important to note that a call to function + <a href="../func/init.html#cdKillCanvas"><font face="Courier"><strong> + cdKillCanvas</strong></font></a> is required to <b>close</b> the file properly.</p> + <p><strong>Coding -</strong> The CGM format supports binary and text coding. If you are not sure what to do, use + binary coding, which is the default. Should you prefer text coding, add a "<font face="Courier">-t</font>" string to + the <font face="Courier">Data</font> parameter.</p> + <p><strong>Precision of Coordinates -</strong> The primitives can use coordinates in real numbers. However, for + compatibility reasons, we use coordinates in integers.</p> + +<h3>Behavior of Functions</h3> +<h4>Control </h4> +<ul> + <li><a href="../func/control.html#cdClear"><font face="Courier"><strong>Clear</strong></font></a>: + does nothing.</li> + <li><a href="../func/control.html#cdFlush"><font face="Courier"><strong>Flush</strong></font></a>: + creates a new image, preserving the previous one. The CGM format supports multiple images in a file.</li> + <li><a href="../func/other.html#cdPlay"><font face="Courier"><strong>Play</strong></font></a>: + works with files created with text or binary coding. There are several callbacks for this driver. If one of the + callbacks returns a value different from zero, <font face="Courier">cdPlay</font>'s processing is interrupted. The + driver implements the callback <tt><strong><font face="Courier">CD_SIZECB</font> </strong></tt>and other callbacks + associated to CGM:<br> + <tt><font face="Courier"><strong>CD_COUNTERCB</strong></font> - int(*cdcgmcountercb)(cdContext *driver, double + percent) - </tt>Executed for each header of CGM commands; returns the percentage (0-100%) of headers read.<br> + <font face="Times New Roman"><code><strong><span style="font-family: Courier">CD_SCLMDECB</span></strong></code></font><tt> - int(*cdcgmsclmdecb)(cdContext + *driver, short scl_mde, short *drw_mode, double *factor)</tt> <font face="Courier">-</font> Executed for the command + CGM SCALE MODE. Returns the current CGM scale mode and allows the callback to modify the scale mode used by the + <font face="Courier">cdPlay</font> function <font face="Courier">(ABSTRACT=0, METRIC=1)</font>. Should you choose the + METRIC or ABSTRACT scale mode but the original scale mode is METRIC, you must provide the conversion factor in mm per + pixel.<br> + <font face="Times New Roman"><code><strong><span style="font-family: Courier">CD_VDCEXTCB</span></strong></code></font><tt> - int(*cdcgmvdcextcb)(cdContext + *driver, short type, void *xmn, void *ymn, void *xmx, void *ymx)</tt> <font face="Courier">-</font> Executed for the + CGM command CGM VDC EXTENT, returns the VDC SPACE. <br> + <font face="Times New Roman"><code><strong><span style="font-family: Courier">CD_BEGPICTCB</span></strong></code></font><tt> - int(*cdcgmbegpictcb)(cdContext + *driver, char *pict)</tt> <font face="Courier">-</font> Executed for the command BEGIN PICTURE, returns the string + that describes the image.<br> + <font face="Times New Roman"><code><strong><span style="font-family: Courier">CD_BEGPICTBCB</span></strong></code></font><tt> - int(*cdcgmbegpictbcb)(cdContext + *driver)</tt> <font face="Courier">-</font> Executed for the command BEGIN PICTURE BODY.<br> + <font face="Times New Roman"><code><strong><span style="font-family: Courier">CD_CGMBEGMTFCB</span></strong></code></font> - <font face="Times New Roman"><code> + int (*cdcgmbegmtfcb)(cdContext *driver, int *xmin, int *ymin, int *xmax, int *ymax)</code></font> - Executed for the + command BEGIN METAFILE, provides the drawing limits of the image in the file.</li> +</ul> +<h4>Coordinate System and Clipping</h4> +<ul> + <li><a href="../func/coordinates.html#cdUpdateYAxis"><font face="Courier"> + <strong>UpdateYAxis</strong></font></a>: does nothing. The axis orientation is the same as the CD library.</li> + <li><b>Complex Regions</b>: not supported.</li> + <li><strong>Transformation Matrix</strong>: not supported.</li> +</ul> +<h4>Primitives</h4> +<ul> + <li><a href="../func/lines.html#cdBegin"><font face="Courier"><strong>Begin</strong></font></a>: + if parameter <strong><tt>CD_CLIP</tt></strong> or <strong><tt>CD_BEZIER</tt></strong> are specified, does nothing.</li> + <li><font face="Courier"><strong><a href="../func/marks.html#cdPixel">Pixel</a></strong></font>: + does not exist in CGM, is simulated using a mark with size 1.</li> + <li><strong><font face="Courier"><a href="../func/filled.html#cdChord">Chord</a></font></strong>: + does nothing.</li> + <li>Floating point primitives are supported.</li> +</ul> +<h4>Attributes </h4> +<ul> + <li><a href="../func/attributes.html#cdWriteMode"><font face="Courier"> + <strong> + WriteMode</strong></font></a>: does nothing, returns <font face="Courier">CD_REPLACE</font>.</li> + <li><a href="../func/text.html#cdFontDim"><font face="Courier"><strong>FontDim</strong></font></a>: + is simulated.</li> + <li><a href="../func/filled.html#cdFillMode"><font face="Courier"><strong> + FillMode</strong></font></a>: does nothing.</li> + <li><a href="../func/filled.html#cdLineCap"><font face="Courier"><strong> + LineCap</strong></font></a>: does nothing.</li> + <li><a href="../func/filled.html#cdLineJoin"><font face="Courier"><strong> + LineJoin</strong></font></a>: does nothing.</li> + <li><a href="../func/text.html#cdTextSize"><font face="Courier"><strong> + TextSize</strong></font></a>: is simulated.</li> + <li><a href="../func/text.html#cdTextOrientation"><font face="Courier"> + <strong> + TextOrientation</strong></font></a>: does nothing.</li> + <li><a href="../func/text.html#cdFont"><font face="Courier"><strong>Font</strong></font></a>: + see the table bellow for the generated font names. No other fonts are + supported.</li> +</ul> +<div align="center"> + <center> + <table border="1" cellpadding="5"> + <caption style="text-align: center"><font size="4">Font Mapping</font></caption> + <tr> + <th rowspan="2">CD Fonts</th> + <th colspan="4">Generated Font Names</th> + </tr> + <tr> + <th>CD_PLAIN</th> + <th>CD_BOLD</th> + <th>CD_ITALIC</th> + <th>CD_BOLD|CD_ITALIC</th> + </tr> + <tr> + <td>"System"</td> + <td>"SYSTEM"</td> + <td>"SYSTEM_BOLD"</td> + <td>"SYSTEM_ITALIC"</td> + <td>"SYSTEM_BOLDITALIC"</td> + </tr> + <tr> + <td>"Courier"</td> + <td>"COURIER" </td> + <td>"COURIER_BOLD" </td> + <td>"COURIER_ITALIC" </td> + <td>"COURIER_BOLDITALIC"</td> + </tr> + <tr> + <td>"Times"</td> + <td>"TIMES_ROMAN" </td> + <td>"TIMES_ROMAN_BOLD"</td> + <td>"TIMES_ROMAN_ITALIC"</td> + <td>"TIMES_ROMAN_BOLDITALIC" </td> + </tr> + <tr> + <td>"Helvetica"</td> + <td>"HELVETICA" </td> + <td>"HELVETICA_BOLD"</td> + <td>"HELVETICA_ITALIC"</td> + <td>"HELVETICA_BOLDITALIC"</td> + </tr> + </table> + </center> +</div> +<h4>Colors </h4> +<ul> + <li><a href="../func/color.html#cdGetColorPlanes"><font face="Courier"> + <strong> + GetColorPlanes</strong></font></a>: returns 24.</li> + <li><a href="../func/color.html#cdPalette"><font face="Courier"><strong>Palette</strong></font></a>: + does nothing. </li> +</ul> +<h4>Client Images </h4> +<ul> + <li><a href="../func/client.html#cdGetImageRGB"><font face="Courier"><strong> + GetImageRGB</strong></font></a>: does nothing.</li> + <li><a href="../func/client.html#cdPutImageRGBA"><font face="Courier"><strong> + PutImageRGBA</strong></font></a>: alpha is ignored.</li> +</ul> +<h4>Server Images</h4> +<ul> + <li>All functions do nothing.</li> +</ul> + +</body> + +</html> |