From adc6b217669b30f4396e8a89f2a15b679d0e313e Mon Sep 17 00:00:00 2001
From: fanboimsft <fanboimsft@icloud.com>
Date: Thu, 21 Dec 2017 23:21:53 +0700
Subject: [PATCH] alpha patch to latest git version

---
 config.def.h |  6 ++++-
 config.mk    |  4 ++--
 st.h         |  1 +
 win.h        |  4 ++++
 x.c          | 71 +++++++++++++++++++++++++++++++++++++++++++++++++++++-------
 5 files changed, 75 insertions(+), 11 deletions(-)

diff --git a/config.def.h b/config.def.h
index 877afab..0e423b1 100644
--- a/config.def.h
+++ b/config.def.h
@@ -82,6 +82,9 @@ char termname[] = "st-256color";
  */
 static unsigned int tabspaces = 8;
 
+/* bg opacity */
+unsigned int alpha = 0xcc;
+
 /* Terminal colors (16 first used in escape sequence) */
 const char *colorname[] = {
 	/* 8 normal colors */
@@ -109,6 +112,7 @@ const char *colorname[] = {
 	/* more colors can be added after 255 to use with DefaultXX */
 	"#cccccc",
 	"#555555",
+	"black",
 };
 
 
@@ -117,7 +121,7 @@ const char *colorname[] = {
  * foreground, background, cursor, reverse cursor
  */
 unsigned int defaultfg = 7;
-unsigned int defaultbg = 0;
+unsigned int defaultbg = 257;
 unsigned int defaultcs = 256;
 unsigned int defaultrcs = 257;
 
diff --git a/config.mk b/config.mk
index 0aceec4..d2421f8 100644
--- a/config.mk
+++ b/config.mk
@@ -11,10 +11,10 @@ X11INC = /usr/X11R6/include
 X11LIB = /usr/X11R6/lib
 
 # includes and libs
-INCS = -I$(X11INC) \
+INCS = -I. -I/usr/include -I${X11INC} \
        `pkg-config --cflags fontconfig` \
        `pkg-config --cflags freetype2`
-LIBS = -L$(X11LIB) -lm -lrt -lX11 -lutil -lXft \
+LIBS = -L/usr/lib -lc -L${X11LIB} -lm -lrt -lX11 -lutil -lXft -lXrender\
        `pkg-config --libs fontconfig` \
        `pkg-config --libs freetype2`
 
diff --git a/st.h b/st.h
index 44d4938..180fdba 100644
--- a/st.h
+++ b/st.h
@@ -251,6 +251,7 @@ extern unsigned int blinktimeout;
 extern char termname[];
 extern const char *colorname[];
 extern size_t colornamelen;
+extern unsigned int alpha;
 extern unsigned int defaultfg;
 extern unsigned int defaultbg;
 extern unsigned int defaultcs;
diff --git a/win.h b/win.h
index 428111c..05e8482 100644
--- a/win.h
+++ b/win.h
@@ -5,6 +5,10 @@
 #define XK_NO_MOD     0
 #define XK_SWITCH_MOD (1<<13)
 
+/* alpha */
+#define OPAQUE 0Xff
+#define USE_ARGB (alpha != OPAQUE && opt_embed == NULL)
+
 typedef XftGlyphFontSpec GlyphFontSpec;
 
 void draw(void);
diff --git a/x.c b/x.c
index 191e5dc..0e12ab9 100644
--- a/x.c
+++ b/x.c
@@ -49,6 +49,7 @@ typedef struct {
 	XSetWindowAttributes attrs;
 	int scr;
 	int isfixed; /* is fixed geometry? */
+	int depth; /* bit depth */
 	int l, t; /* left and top offset */
 	int gm; /* geometry mask */
 } XWindow;
@@ -562,7 +563,7 @@ xresize(int col, int row)
 
 	XFreePixmap(xw.dpy, xw.buf);
 	xw.buf = XCreatePixmap(xw.dpy, xw.win, win.w, win.h,
-			DefaultDepth(xw.dpy, xw.scr));
+			xw.depth);
 	XftDrawChange(xw.draw, xw.buf);
 	xclear(0, 0, win.w, win.h);
 }
@@ -619,6 +620,13 @@ xloadcols(void)
 			else
 				die("Could not allocate color %d\n", i);
 		}
+
+	/* set alpha value of bg color */
+	if (USE_ARGB) {
+		dc.col[defaultbg].color.alpha = (0xffff * alpha) / OPAQUE;
+		dc.col[defaultbg].pixel &= 0x00111111;
+		dc.col[defaultbg].pixel |= alpha << 24;
+	}
 	loaded = 1;
 }
 
@@ -640,6 +648,17 @@ xsetcolorname(int x, const char *name)
 	return 0;
 }
 
+void
+xtermclear(int col1, int row1, int col2, int row2)
+{
+	XftDrawRect(xw.draw,
+			&dc.col[IS_SET(MODE_REVERSE) ? defaultfg : defaultbg],
+			borderpx + col1 * win.cw,
+			borderpx + row1 * win.ch,
+			(col2-col1+1) * win.cw,
+			(row2-row1+1) * win.ch);
+}
+
 /*
  * Absolute coordinates.
  */
@@ -879,7 +898,40 @@ 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())
@@ -889,7 +941,11 @@ 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 */
@@ -912,16 +968,15 @@ xinit(void)
 	if (!(opt_embed && (parent = strtol(opt_embed, NULL, 0))))
 		parent = XRootWindow(xw.dpy, xw.scr);
 	xw.win = XCreateWindow(xw.dpy, parent, xw.l, xw.t,
-			win.w, win.h, 0, XDefaultDepth(xw.dpy, xw.scr), InputOutput,
+			win.w, win.h, 0, xw.depth, InputOutput,
 			xw.vis, CWBackPixel | CWBorderPixel | CWBitGravity
 			| CWEventMask | CWColormap, &xw.attrs);
 
 	memset(&gcvalues, 0, sizeof(gcvalues));
 	gcvalues.graphics_exposures = False;
-	dc.gc = XCreateGC(xw.dpy, parent, GCGraphicsExposures,
-			&gcvalues);
-	xw.buf = XCreatePixmap(xw.dpy, xw.win, win.w, win.h,
-			DefaultDepth(xw.dpy, xw.scr));
+	xw.buf = XCreatePixmap(xw.dpy, xw.win, win.w, win.h, xw.depth);
+	dc.gc = XCreateGC(xw.dpy, (USE_ARGB) ? xw.buf: parent,
+			GCGraphicsExposures, &gcvalues);
 	XSetForeground(xw.dpy, dc.gc, dc.col[defaultbg].pixel);
 	XFillRectangle(xw.dpy, xw.buf, dc.gc, 0, 0, win.w, win.h);
 
-- 
2.15.0