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diff --git a/html/en/drv/xwin.html b/html/en/drv/xwin.html new file mode 100644 index 0000000..cd2d900 --- /dev/null +++ b/html/en/drv/xwin.html @@ -0,0 +1,129 @@ +<!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>X-Windows</title> +<link rel="stylesheet" type="text/css" href="../../style.css"> +<style type="text/css"> +.style1 { + font-family: Courier; +} +</style> +</head> + +<body> + +<h2>X-Windows Base Driver</h2> + + <p>This driver represents a basic driver for all system-dependent drivers + implemented in the X-Windows system. The implementation uses the XLIB API + functions. It was developed using X11R4, but works in more recent versions, + such as X11R6.</p> + <p>Note: The coordinates internally implemented by the video driver use 16-bit + integers. Therefore, if a coordinate with less than -32k or more than 32k is + defined, it will be interpreted incorrectly.</p> + +<h3>Behavior of Functions</h3> +<h4>Control </h4> +<ul> + <li><a href="../func/other.html#cdPlay"> + <font face="Courier"><strong>Play</strong></font></a>: does nothing, returns + <font face="Courier">CD_ERROR</font>. </li> +</ul> +<h4>Coordinate System and Clipping </h4> +<ul> + <li> + <a href="../func/coordinates.html#cdUpdateYAxis"> + <font face="Courier"><strong>UpdateYAxis</strong></font></a>: the + orientation of axis Y is the opposite to its orientation in the CD library.</li> +</ul> +<h4>Primitives</h4> +<ul> + <li><a href="../func/text.html#cdText"><font face="Courier"><strong>Text</strong></font></a>: + text orientation is simulated using XVertex rotines. Generic transformation + matrix affects only the position of the text.</li> + <li><a href="../func/lines.html#cdBegin"> + <font face="Courier"><strong>Begin</strong></font></a>: Filled + polygons have an error of one pixel to the right and below. <strong><tt> + CD_BEZIER</tt></strong> is simulated with lines.</li> + <li><span class="style1"><a href="../func/marks.html#cdMark"> + <strong>Box</strong></a></span>: in Linux with ATI board, is being drawn with one + extra pixel to the right and below.</li> +</ul> +<h4>Attributes </h4> +<ul> + <li> + <a href="../func/lines.html#cdLineWidth"> + <font face="Courier"><strong>LineWidth</strong></font></a>: if + <font face="Courier">width</font> is 1, the driver will use 0 for a better + performance.</li> + <li> + <a href="../func/lines.html#cdLineStyle"> + <font face="Courier"><strong>LineStyle</strong></font></a>: thick lines have + style only in the line's direction. For example, you will see small rectangles + in a thick dotted line.</li> + <li> + <a href="../func/text.html#cdNativeFont"> + <font face="Courier"><strong>NativeFont</strong></font></a>: also accepts the + X-Windows font string format. You can use program <strong>xfontsel</strong> to select a font and obtain the string. + For ex: "-*-times-bold-r-*-*-24-*-*-*-*-*-*-*" (equivalent of <strong>Font</strong>("Times", + CD_BOLD, -24).</li> + <li><a href="../func/text.html#cdFont"> + <font face="Courier"><strong>Font</strong></font></a>: the old name "System" + is mapped to "fixed".</li> +</ul> +<h4>Colors </h4> +<ul> + <li> + <a href="../func/color.html#cdPalette"> + <font face="Courier"><strong>Palette</strong></font></a>: When the number of + bits per pixel is smaller than or equal to 8, the driver will use the system + palette to solve colors passed as parameters to the canvas. The driver + allocates colors as they are requested - if a color cannot be allocated, the + closest color is used in the palette. For such, the driver sees all available + colors, in the current application and others. If one of the applications is + terminated, a color in the palette may become invalid and will only be updated + by the driver when it is requested again. For this reason, a call to <strong> + cdForeground </strong>or <strong>cdBackground</strong> or <strong>cdPalette</strong> + is recommended before drawing.<br> + When CD_FORCE is used, the driver forces color allocation in the X server. + This may imply changing colors in other applications when a cursor moves in + and out of the canvas. However, if the number of requested colors is smaller + than the maximum number of possible colors in the palette, then the first + colors in the default system palette will be preserved, minimizing this + problem.<br> + When CD_POLITE is used, all colors allocated by the driver are liberated, and + the requested colors are allocated. This is useful for the application to + prioritize the colors that will be allocated, causing other colors to be + mapped to their closest colors.<br> + Note that canvases in the same application interfere with one another, but + when a canvas is terminated it liberates all allocated colors.</li> +</ul> +<h4>Client Images</h4> +<ul> + <li> + <a href="../func/client.html#cdGetImageRGB"> + <font face="Courier"><strong>GetImageRGB</strong></font></a>: can be very + slow due to the heavy conversions performed to translate data in system format + into RGB vectors. </li> +</ul> +<h4>Exclusive Attributes</h4> +<ul> + <li>"<b><font face="Courier">GC</font></b>": returns the X11 graphics + context (get only). In Lua is returned as a user data.</li> +</ul> + +<ul> + <li>"<b><font face="Courier">ROTATE</font></b>": allows the usage of 1 + angle and 1 coordinate (x, y), that define a global rotation transformation + centered in the specified coordinate. Use 1 real and 2 integer values inside a + string ("%g %d %d" = angle x y). In this driver will change the + current transformation matrix, if removed will reset the current + transformation matrix.</li> +</ul> + +</body> + +</html> |