Function PSL_plottextline

src/postscriptlight.c:5769–5862

}

int PSL_plottextline (struct PSL_CTRL *PSL, double x[], double y[], int np[], int n_segments, void *arg1, void *arg2, char *label[], double angle[], int nlabel_per_seg[], double fontsize, int justify, double offset[], int mode) {
	/* Placing text along lines, setting up text clippaths, and drawing the lines */
	/* x,y		Array containing the concatenated label path of all segments
	 * np		Array containing length of each label path segment in concatenated path
	 * n_segments	Number of line segments
	 * arg1, arg2   These are pointers to two arrays, depending on whether we have curved or straight baselines:
	 *  If curved baselines then
	 *  arg1 = node		Index into x/y array of label plot positions per segment (i.e., start from 0 for each new segment)
	 *  arg2 = NULL		Not used
	 *  If straight text baselines then
	 *  arg1 = xp		Array of x coordinates of where labels will be placed
	 *  arg2 = yp		Array of y coordinates of where labels will be placed
	 * label	Array of text labels
	 * angle	Text angle for each label
	 * nlabel_per_seg	Array containing number of labels per segment
	 * fontsize	Constant fontsize of all label texts [font use is the current font set with PSL_setfont]
	 * just		Justification of text relative to label coordinates [constant for all labels]
	 * offset	Clearances between text and textbox [constant]
	 * mode		= 1: We place all the PSL variables required to use the text for clipping of painting.
	 * 			= 2: We paint the text that is stored in the PSL variables.
	 * 			= 4: We use the text stored in the PSL variables to set up a clip path.  Clipping is turned ON.
	 * 			= 8: We draw the paths.
	 * 			= 16: We turn clip path OFF.
	 * 			= 32: We want rounded rectangles instead of straight rectangular boxes [straight text only].
	 * 			= 64: Typeset text along path [straight text].
	 * 			= 128: Fill box
	 * 			= 256: Draw box
	 * 			= 512: Fill & outline font, fill first, then outline
	 * 			= 1024: Fill & outline font, outline first, then fill
	 */

	bool curved = ((mode & PSL_TXT_CURVED) == PSL_TXT_CURVED);	/* True if baseline must follow line path */
	int extras, kind = (curved) ? 1 : 0;
	char *name[2] = {"straight", "curved"}, *ext[2] = {"clip", "labels"};

	if (mode & 1) {	/* Lay down PSL variables */
		int i = 0, n_labels = 0;

		if (n_segments <= 0) return (PSL_NO_ERROR);	/* Nothing to do yet */
		if (fontsize == 0.0) return (PSL_NO_ERROR);	/* Nothing to do if text has zero size */

		if (justify < 0) psl_remove_spaces (label, n_segments, nlabel_per_seg);	/* Strip leading and trailing spaces */
		for (i = 0; i < n_segments; i++) n_labels += nlabel_per_seg[i];	/* Count number of labels */

		/* Set clearance and text height parameters */
		PSL_comment (PSL, "Set constants for textbox clearance:\n");
		PSL_defunits (PSL, "PSL_gap_x", offset[0]);		/* Set text clearance in x direction */
		PSL_defunits (PSL, "PSL_gap_y", offset[1]);		/* Set text clearance in y direction */

		/* Set PSL arrays and constants for this set of lines and labels */
		if (curved)	/* Set PSL array for curved baselines [also used to draw lines if selected] */
			psl_set_reducedpath_arrays (PSL, x, y, n_segments, np, nlabel_per_seg, arg1);
		psl_set_attr_arrays (PSL, (curved) ? arg1 : NULL, angle, label, n_segments, nlabel_per_seg);
		psl_set_int_array   (PSL, "label_n", nlabel_per_seg, n_segments);
		PSL_definteger (PSL, "PSL_n_paths", n_segments);
		PSL_definteger (PSL, "PSL_n_labels", n_labels);
		if (!curved)	/* Set PSL array for text location with straight baselines */
			psl_set_path_arrays (PSL, "txt", arg1, arg2, 1, &n_labels);