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diff --git a/html/en/func/coordinates.html b/html/en/func/coordinates.html new file mode 100644 index 0000000..9f119bb --- /dev/null +++ b/html/en/func/coordinates.html @@ -0,0 +1,148 @@ +<!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>Coordinate System</title> +<link rel="stylesheet" type="text/css" href="../../style.css"> +</head> + +<body> + +<h2 align="center">Coordinate System</h2> +<pre class="function"><span class="mainFunction">void <a name="cdGetCanvasSize">cdCanvasGetSize</a>(cdCanvas* canvas, int *width, int *height, double *width_mm, double *height_mm); [in C]</span> + +canvas:GetSize() -> (width, height, mm_width, mm_height: number) [in Lua]</pre> + + <p>Returns the canvas size in pixels and in millimeters. You can provide only + the desired values and <font>NULL</font> for the others.</p> + +<pre class="function"><span class="mainFunction">int <a name="cdUpdateYAxis">cdCanvasUpdateYAxis</a>(cdCanvas* canvas, int *y); [in C]</span> +double cdfCanvasUpdateYAxis(cdCanvas* canvas, double *y); [in C] +int cdCanvasInvertYAxis(cdCanvas* canvas, int y); [in C] +double cdfCanvasInvertYAxis(cdCanvas* canvas, double y); [in C] + +canvas:UpdateYAxis(yc: number) -> (yr: number) [in Lua] +canvas:InvertYAxis(yc: number) -> (yr: number) [in Lua]</pre> + + <p>In some graph systems, the origin is at the upper left corner of the + canvas, with the direction of the Y axis pointing down. In this case, the + function converts the coordinate system of the CD library into the internal + system of the active canvas' driver, and the other way round. If this is not + the case, nothing happens. This is just <font>"y = height-1 - + y"</font>. It returns the changed value. The "Invert" will always invert + the given value, the "Update" function will invert only if the canvas has the + Y axis inverted.</p> + +<pre class="function"><span class="mainFunction">void cdCanvasMM2Pixel(cdCanvas* canvas, double mm_dx, double mm_dy, int *dx, int *dy); [in C]</span> +void cdfCanvasMM2Pixel(cdCanvas* canvas, double mm_dx, double mm_dy, double *dx, double *dy); [in C] + +canvas:MM2Pixel(mm_dx, mm_dy: number) -> (dx, dy: number) [in Lua] +canvas:fMM2Pixel(mm_dx, mm_dy: number) -> (dx, dy: number) [in Lua]</pre> + + <p>Converts sizes in millimeters into pixels (canvas coordinates). You can + provide only the desired values and <font>NULL</font> for the + others.</p> + +<pre class="function"><span class="mainFunction">void cdCanvasPixel2MM(cdCanvas* canvas, int dx, int dy, double *mm_dx, double *mm_dy); [in C]</span> +void cdfCanvasPixel2MM(cdCanvas* canvas, double dx, double dy, double *mm_dx, double *mm_dy); [in C] + +canvas:Pixel2MM(dx, dy: number) -> (mm_dx, mm_dy: number) [in Lua] +canvas:fPixel2MM(dx, dy: number) -> (mm_dx, mm_dy: number) [in Lua]</pre> + + <p>Converts sizes in pixels (canvas coordinates) into millimeters. You can + provide only the desired values and <font>NULL</font> for the + others. Use this function to obtain the horizontal and vertical resolution of + the canvas by passing 1 as parameter in <font>dx</font> and + <font>dy</font>. The resolution value is obtained using the + formula <strong><font>res=1.0/mm</font></strong>.</p> + +<pre class="function"><span class="mainFunction">void cdCanvasOrigin(cdCanvas* canvas, int x, int y); [in C]</span> +void cdfCanvasOrigin(cdCanvas* canvas, double x, double y); [in C] + +canvas:Origin(x, y: number) [in Lua] +canvas:fOrigin(x, y: number) [in Lua]</pre> + + <p>Allows translating the origin - for instance, to the center of the canvas. + The function profits from the architecture of the library to simulate a + translation of the origin, which in fact is never actually passed to the + canvas in the respective driver. Default values: (0, 0)</p> + + +<pre class="function"><span class="mainFunction">void cdCanvasGetOrigin(cdCanvas* canvas, int *x, int *y); [in C]</span> +void cdfCanvasGetOrigin(cdCanvas* canvas, double *x, double *y); [in C] + +canvas:GetOrigin() -> (x, y: number) [in Lua] +canvas:fGetOrigin() -> (x, y: number) [in Lua]</pre> + + <p>Returns the origin.</p> + + +<h3>Transformation Matrix</h3> + +<pre class="function"><span class="mainFunction">void <a name="cdTransform">cdCanvasTransform</a>(cdCanvas* canvas, const double* matrix); [in C]</span> + +canvas:Transform(matrix: table) [in Lua]</pre> + + <p>Defines a transformation matrix with 6 elements. If the matrix is NULL, + the + transformation is reset to the identity. Default value: NULL.</p> + <p>The matrix contains scale, rotation and translation elements as follows:</p> + <pre>|x'| |sx*cos(angle) -sin(angle) dx| |x| |0 2 4| +|y'| = | sin(angle) sy*cos(angle) dy| * |y| with indices |1 3 5| + |1|</pre> + <p>But notice that the indices are different of the <strong> + cdCanvasVectorTextTransform</strong>.</p> +<p>Functions that retrieve images from the canvas are not affected by the +transformation matrix, such as <strong>GetImage</strong>, <strong>GetImageRGB</strong> +and <strong>ScrollArea</strong>.</p> +<p>Transformation matrix is independent of the <strong>World Coordinate</strong> +and <strong>Origin</strong> +functions. And those are affected if a transformation is set, just like other +regular primitives.</p> + + +<pre class="function"><span class="mainFunction">double* <a name="cdGetTransform">cdCanvasGetTransform</a>(cdCanvas* canvas); [in C]</span> + +canvas:GetTransformation() -> (matrix: table) [in Lua]</pre> + + <p>Returns the transformation matrix. If the identity is set, returns NULL.</p> + + +<pre class="function"><span class="mainFunction">void <a name="cdTransformMultiply">cdCanvasTransforMultiply</a>(cdCanvas* canvas, const double* matrix); [in C]</span> + +canvas:TransformMultiply(matrix: table) [in Lua]</pre> + + <p>Left multiply the current transformation by the given transformation.</p> + +<pre class="function"><span class="mainFunction">void <a name="cdTransformTranslate">cdCanvasTransformTranslate</a>(cdCanvas* canvas, double dx, double dy); [in C]</span> + +canvas:TransformTranslate(dx, dy: number) [in Lua]</pre> + + <p>Applies a translation to the current transformation.</p> + +<pre class="function"><span class="mainFunction">void <a name="cdTransformScale">cdCanvasTransformScale</a>(cdCanvas* canvas, double sx, double sy); [in C]</span> + +canvas:TransformScale(sx, sy: number) [in Lua]</pre> + + <p>Applies a scale to the current transformation.</p> + +<pre class="function"><span class="mainFunction">void <a name="cdTransformRotate">cdCanvasTransformRotate</a>(cdCanvas* canvas, double angle); [in C]</span> + +canvas:TransformRotate(angle: number) [in Lua]</pre> + + <p>Applies a rotation to the current transformation. Angle is in degrees, + oriented counter-clockwise from the horizontal axis.</p> + +<pre class="function"><span class="mainFunction">void <a name="cdTransformPoint">cdCanvasTransformPoint</a>(cdCanvas* canvas, int x, int y, int *tx, int *ty); [in C]</span> +void cdfCanvasTransformPoint(cdCanvas* canvas, double x, double y, double *tx, double *ty); [in C] + +canvas:TransformPoint(x, y: number) -> (tx, ty: number) [in Lua] +canvas:fTransformPoint(x, y: number) -> (tx, ty: number) [in Lua]</pre> + + <p>Applies a transformation to a given point.</p> + +</body> + +</html>
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