[dev] [st] [patch] ARGB background for st-0.4.1

From: Eon S. Jeon <esjeon_AT_live.com>
Date: Tue, 11 Jun 2013 20:44:35 -0400

Hi.

I've made a short patch that enables semi-transparent background for
st-0.4.1. The same mechanism should work with recent commits.

Some important notes:
1) This changes background opacity only.
2) The color designated by "defaultbg" are modified during the
initialization, so you should add another color to be used as
background. (check st.c:2360 to see what actually happens)
3) There's a bug in this patch: if st is embeded into an ARGB-enabled
window, it crashes. (What an irony.)
4) The maximum value of 'alpha' is 0xff (= OPAQUE)

Regards

Eon

P.S: I'm really sorry for the mess. It was a huge mistake to use live.com... :'(


diff --git a/config.def.h b/config.def.h
index d1c20bd..cc9f34d 100644
--- a/config.def.h
+++ b/config.def.h
_AT_@ -25,6 +25,8 @@ static char termname[] = "st-256color";

 static unsigned int tabspaces = 8;

+/* background opacity */
+static const int alpha = 0xdd;

 /* Terminal colors (16 first used in escape sequence) */
 static const char *colorname[] = {
_AT_@ -52,6 +54,7 @@ static const char *colorname[] = {

     /* more colors can be added after 255 to use with DefaultXX */
     "#cccccc",
+ "black",
 };


_AT_@ -60,7 +63,7 @@ static const char *colorname[] = {
  * foreground, background, cursor
  */
 static unsigned int defaultfg = 7;
-static unsigned int defaultbg = 0;
+static unsigned int defaultbg = 257;
 static unsigned int defaultcs = 256;

 /*
diff --git a/config.mk b/config.mk
index 9431de2..0b92bf2 100644
--- a/config.mk
+++ b/config.mk
_AT_@ -14,7 +14,7 @@ X11LIB = /usr/X11R6/lib
 INCS = -I. -I/usr/include -I${X11INC} \
        `pkg-config --cflags fontconfig` \
        `pkg-config --cflags freetype2`
-LIBS = -L/usr/lib -lc -L${X11LIB} -lX11 -lutil -lXext -lXft \
+LIBS = -L/usr/lib -lc -L${X11LIB} -lX11 -lutil -lXext -lXft -lXrender \
        `pkg-config --libs fontconfig` \
        `pkg-config --libs freetype2`

diff --git a/st.c b/st.c
index 686ed5d..de4d0f9 100644
--- a/st.c
+++ b/st.c
_AT_@ -60,6 +60,7 @@ char *argv0;
 #define XK_ANY_MOD UINT_MAX
 #define XK_NO_MOD 0
 #define XK_SWITCH_MOD (1<<13)
+#define OPAQUE 0Xff

 #define REDRAW_TIMEOUT (80*1000) /* 80 ms */

_AT_@ -74,6 +75,7 @@ char *argv0;
 #define ATTRCMP(a, b) ((a).mode != (b).mode || (a).fg != (b).fg ||
(a).bg != (b).bg)
 #define IS_SET(flag) ((term.mode & (flag)) != 0)
 #define TIMEDIFF(t1, t2) ((t1.tv_sec-t2.tv_sec)*1000 +
(t1.tv_usec-t2.tv_usec)/1000)
+#define USE_ARGB (alpha != OPAQUE && opt_embed == NULL)

 #define VT102ID "\033[?6c"

_AT_@ -215,6 +217,7 @@ typedef struct {
     int w, h; /* window width and height */
     int ch; /* char height */
     int cw; /* char width */
+ int depth; /* bit depth */
     char state; /* focus, redraw, visible */
 } XWindow;

_AT_@ -2335,8 +2338,7 @@ xresize(int col, int row) {
     xw.th = MAX(1, row * xw.ch);

     XFreePixmap(xw.dpy, xw.buf);
- xw.buf = XCreatePixmap(xw.dpy, xw.win, xw.w, xw.h,
- DefaultDepth(xw.dpy, xw.scr));
+ xw.buf = XCreatePixmap(xw.dpy, xw.win, xw.w, xw.h, xw.depth);
     XftDrawChange(xw.draw, xw.buf);
     xclear(0, 0, xw.w, xw.h);
 }
_AT_@ -2360,6 +2362,13 @@ xloadcols(void) {
         }
     }

+ /* set alpha value of bg color */
+ if (USE_ARGB) {
+ dc.col[defaultbg].color.alpha = (0xffff * alpha) / OPAQUE; //0xcccc;
+ dc.col[defaultbg].pixel &= 0x00111111;
+ dc.col[defaultbg].pixel |= alpha << 24; // 0xcc000000;
+ }
+
     /* load colors [16-255] ; same colors as xterm */
     for(i = 16, r = 0; r < 6; r++) {
         for(g = 0; g < 6; g++) {
_AT_@ -2603,7 +2612,38 @@ xinit(void) {
     if(!(xw.dpy = XOpenDisplay(NULL)))
         die("Can't open display\n");
     xw.scr = XDefaultScreen(xw.dpy);
- xw.vis = XDefaultVisual(xw.dpy, xw.scr);
+ xw.depth = (USE_ARGB)? 32: XDefaultDepth(xw.dpy, xw.scr);
+ if (! USE_ARGB)
+ xw.vis = XDefaultVisual(xw.dpy, xw.scr);
+ else {
+ XVisualInfo *vis;
+ XRenderPictFormat *fmt;
+ int nvi;
+ int i;
+
+ XVisualInfo tpl = {
+ .screen = xw.scr,
+ .depth = 32,
+ .class = TrueColor
+ };
+
+ vis = XGetVisualInfo(xw.dpy, VisualScreenMask |
VisualDepthMask | VisualClassMask, &tpl, &nvi);
+ xw.vis = NULL;
+ for(i = 0; i < nvi; i ++) {
+ fmt = XRenderFindVisualFormat(xw.dpy, vis[i].visual);
+ if (fmt->type == PictTypeDirect && fmt->direct.alphaMask) {
+ xw.vis = vis[i].visual;
+ break;
+ }
+ }
+
+ XFree(vis);
+
+ if (! xw.vis) {
+ fprintf(stderr, "Couldn't find ARGB visual.\n");
+ exit(1);
+ }
+ }

     /* font */
     if(!FcInit())
_AT_@ -2613,7 +2653,10 @@ xinit(void) {
     xloadfonts(usedfont, 0);

     /* colors */
- xw.cmap = XDefaultColormap(xw.dpy, xw.scr);
+ if (! USE_ARGB)
+ xw.cmap = XDefaultColormap(xw.dpy, xw.scr);
+ else
+ xw.cmap = XCreateColormap(xw.dpy, XRootWindow(xw.dpy,
xw.scr), xw.vis, None);
     xloadcols();

     /* adjust fixed window geometry */
_AT_@ -2647,7 +2690,7 @@ xinit(void) {
     parent = opt_embed ? strtol(opt_embed, NULL, 0) : \
             XRootWindow(xw.dpy, xw.scr);
     xw.win = XCreateWindow(xw.dpy, parent, xw.fx, xw.fy,
- xw.w, xw.h, 0, XDefaultDepth(xw.dpy, xw.scr), InputOutput,
+ xw.w, xw.h, 0, xw.depth, InputOutput,
             xw.vis,
             CWBackPixel | CWBorderPixel | CWBitGravity | CWEventMask
             | CWColormap,
_AT_@ -2655,10 +2698,11 @@ xinit(void) {

     memset(&gcvalues, 0, sizeof(gcvalues));
     gcvalues.graphics_exposures = False;
- dc.gc = XCreateGC(xw.dpy, parent, GCGraphicsExposures,
+ xw.buf = XCreatePixmap(xw.dpy, xw.win, xw.w, xw.h, xw.depth);
+ dc.gc = XCreateGC(xw.dpy,
+ (USE_ARGB)? xw.buf: parent,
+ GCGraphicsExposures,
             &gcvalues);
- xw.buf = XCreatePixmap(xw.dpy, xw.win, xw.w, xw.h,
- DefaultDepth(xw.dpy, xw.scr));
     XSetForeground(xw.dpy, dc.gc, dc.col[defaultbg].pixel);
     XFillRectangle(xw.dpy, xw.buf, dc.gc, 0, 0, xw.w, xw.h);
Received on Wed Jun 12 2013 - 02:44:35 CEST