added draw.h, draw.c

2 files changed, 211 insertions, 0 deletions

diff --git a/draw.c b/draw.c
new file mode 100644
index 0000000..341a26f
--- /dev/null
+++ b/draw.c
@@ -0,0 +1,176 @@
+/* See LICENSE file for copyright and license details. */
+#include <locale.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <X11/Xlib.h>
+#include "draw.h"
+
+#define MAX(a, b)  ((a) > (b) ? (a) : (b))
+#define MIN(a, b)  ((a) < (b) ? (a) : (b))
+#define DEFAULTFN  "fixed"
+
+static Bool loadfont(DC *dc, const char *fontstr);
+
+void
+drawrect(DC *dc, int x, int y, unsigned int w, unsigned int h, Bool fill, unsigned long color) {
+	XSetForeground(dc->dpy, dc->gc, color);
+	if(fill)
+		XFillRectangle(dc->dpy, dc->canvas, dc->gc, dc->x + x, dc->y + y, w, h);
+	else
+		XDrawRectangle(dc->dpy, dc->canvas, dc->gc, dc->x + x, dc->y + y, w-1, h-1);
+}
+
+void
+drawtext(DC *dc, const char *text, unsigned long col[ColLast]) {
+	char buf[BUFSIZ];
+	size_t mn, n = strlen(text);
+
+	/* shorten text if necessary */
+	for(mn = MIN(n, sizeof buf); textnw(dc, text, mn) + dc->font.height/2 > dc->w; mn--)
+		if(mn == 0)
+			return;
+	memcpy(buf, text, mn);
+	if(mn < n)
+		for(n = MAX(mn-3, 0); n < mn; buf[n++] = '.');
+
+	drawrect(dc, 0, 0, dc->w, dc->h, True, BG(dc, col));
+	drawtextn(dc, buf, mn, col);
+}
+
+void
+drawtextn(DC *dc, const char *text, size_t n, unsigned long col[ColLast]) {
+	int x = dc->x + dc->font.height/2;
+	int y = dc->y + dc->font.ascent+1;
+
+	XSetForeground(dc->dpy, dc->gc, FG(dc, col));
+	if(dc->font.set)
+		XmbDrawString(dc->dpy, dc->canvas, dc->font.set, dc->gc, x, y, text, n);
+	else {
+		XSetFont(dc->dpy, dc->gc, dc->font.xfont->fid);
+		XDrawString(dc->dpy, dc->canvas, dc->gc, x, y, text, n);
+	}
+}
+
+void
+eprintf(const char *fmt, ...) {
+	va_list ap;
+
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+
+	if(fmt[0] != '\0' && fmt[strlen(fmt)-1] == ':') {
+		fputc(' ', stderr);
+		perror(NULL);
+	}
+	exit(EXIT_FAILURE);
+}
+
+void
+freedc(DC *dc) {
+	if(dc->font.set)
+		XFreeFontSet(dc->dpy, dc->font.set);
+	if(dc->font.xfont)
+		XFreeFont(dc->dpy, dc->font.xfont);
+	if(dc->canvas)
+		XFreePixmap(dc->dpy, dc->canvas);
+	XFreeGC(dc->dpy, dc->gc);
+	XCloseDisplay(dc->dpy);
+	free(dc);
+}
+
+unsigned long
+getcolor(DC *dc, const char *colstr) {
+	Colormap cmap = DefaultColormap(dc->dpy, DefaultScreen(dc->dpy));
+	XColor color;
+
+	if(!XAllocNamedColor(dc->dpy, cmap, colstr, &color, &color))
+		eprintf("cannot allocate color '%s'\n", colstr);
+	return color.pixel;
+}
+
+DC *
+initdc(void) {
+	DC *dc;
+
+	if(!setlocale(LC_CTYPE, "") || !XSupportsLocale())
+		fprintf(stderr, "no locale support\n");
+	if(!(dc = calloc(1, sizeof *dc)))
+		eprintf("cannot malloc %u bytes:", sizeof *dc);
+	if(!(dc->dpy = XOpenDisplay(NULL)))
+		eprintf("cannot open display\n");
+
+	dc->gc = XCreateGC(dc->dpy, DefaultRootWindow(dc->dpy), 0, NULL);
+	XSetLineAttributes(dc->dpy, dc->gc, 1, LineSolid, CapButt, JoinMiter);
+	return dc;
+}
+
+void
+initfont(DC *dc, const char *fontstr) {
+	if(!loadfont(dc, fontstr ? fontstr : DEFAULTFN)) {
+		if(fontstr != NULL)
+			fprintf(stderr, "cannot load font '%s'\n", fontstr);
+		if(fontstr == NULL || !loadfont(dc, DEFAULTFN))
+			eprintf("cannot load font '%s'\n", DEFAULTFN);
+	}
+	dc->font.height = dc->font.ascent + dc->font.descent;
+}
+
+Bool
+loadfont(DC *dc, const char *fontstr) {
+	char *def, **missing, **names;
+	int i, n = 1;
+	XFontStruct **xfonts;
+
+	if(!*fontstr)
+		return False;
+	if((dc->font.set = XCreateFontSet(dc->dpy, fontstr, &missing, &n, &def))) {
+		n = XFontsOfFontSet(dc->font.set, &xfonts, &names);
+	}
+	else {
+		dc->font.xfont = XLoadQueryFont(dc->dpy, fontstr);
+		xfonts = &dc->font.xfont;
+	}
+	for(i = 0; i < n; i++) {
+		dc->font.ascent  = MAX(dc->font.ascent,  xfonts[i]->ascent);
+		dc->font.descent = MAX(dc->font.descent, xfonts[i]->descent);
+		dc->font.width   = MAX(dc->font.width,   xfonts[i]->max_bounds.width);
+	}
+	if(missing)
+		XFreeStringList(missing);
+	return (dc->font.set || dc->font.xfont);
+}
+
+void
+mapdc(DC *dc, Window win, unsigned int w, unsigned int h) {
+	XCopyArea(dc->dpy, dc->canvas, win, dc->gc, 0, 0, w, h, 0, 0);
+}
+
+void
+resizedc(DC *dc, unsigned int w, unsigned int h) {
+	if(dc->canvas)
+		XFreePixmap(dc->dpy, dc->canvas);
+
+	dc->canvas = XCreatePixmap(dc->dpy, DefaultRootWindow(dc->dpy), w, h,
+	                           DefaultDepth(dc->dpy, DefaultScreen(dc->dpy)));
+	dc->w = w;
+	dc->h = h;
+}
+
+int
+textnw(DC *dc, const char *text, size_t len) {
+	if(dc->font.set) {
+		XRectangle r;
+
+		XmbTextExtents(dc->font.set, text, len, NULL, &r);
+		return r.width;
+	}
+	return XTextWidth(dc->font.xfont, text, len);
+}
+
+int
+textw(DC *dc, const char *text) {
+	return textnw(dc, text, strlen(text)) + dc->font.height;
+}
diff --git a/draw.h b/draw.h
new file mode 100644
index 0000000..43a57bf
--- /dev/null
+++ b/draw.h
@@ -0,0 +1,35 @@
+/* See LICENSE file for copyright and license details. */
+
+#define FG(dc, col)  ((col)[(dc)->invert ? ColBG : ColFG])
+#define BG(dc, col)  ((col)[(dc)->invert ? ColFG : ColBG])
+
+enum { ColBG, ColFG, ColBorder, ColLast };
+
+typedef struct {
+	int x, y, w, h;
+	Bool invert;
+	Display *dpy;
+	GC gc;
+	Pixmap canvas;
+	struct {
+		int ascent;
+		int descent;
+		int height;
+		int width;
+		XFontSet set;
+		XFontStruct *xfont;
+	} font;
+} DC;  /* draw context */
+
+void drawrect(DC *dc, int x, int y, unsigned int w, unsigned int h, Bool fill, unsigned long color);
+void drawtext(DC *dc, const char *text, unsigned long col[ColLast]);
+void drawtextn(DC *dc, const char *text, size_t n, unsigned long col[ColLast]);
+void eprintf(const char *fmt, ...);
+void freedc(DC *dc);
+unsigned long getcolor(DC *dc, const char *colstr);
+DC *initdc(void);
+void initfont(DC *dc, const char *fontstr);
+void mapdc(DC *dc, Window win, unsigned int w, unsigned int h);
+void resizedc(DC *dc, unsigned int w, unsigned int h);
+int textnw(DC *dc, const char *text, size_t len);
+int textw(DC *dc, const char *text);