Adding invert patch

README.md

@@ -15,6 +15,8 @@ Refer to [https://st.suckless.org/](https://st.suckless.org/) for details on the
 
 ### Changelog:
 
+2020-03-29 - Added invert patch
+
 2020-03-24 - Upgraded to latest (master) of st (commit 51e19ea11dd42eefed1ca136ee3f6be975f618b1 at the time of writing). Custom changes to make the altscreen mouse scollback patch working.
 
 2020-03-21 - Added font2 patch
@@ -69,6 +71,10 @@ Refer to [https://st.suckless.org/](https://st.suckless.org/) for details on the
    - [hidecursor](https://st.suckless.org/patches/hidecursor/)
       - hides the X cursor whenever a key is pressed and show it back when the mouse is moved in the terminal window
 
+   - [invert](https://st.suckless.org/patches/invert/)
+      - adds a keybinding that lets you invert the current colorscheme of st
+      - this provides a simple way to temporarily switch to a light colorscheme if you use a dark colorscheme or visa-versa
+
    - [iso14755](https://st.suckless.org/patches/iso14755/)
       - pressing the default binding Ctrl+Shift-i will popup dmenu, asking you to enter a unicode codepoint that will be converted to a glyph and then pushed to st
 

config.def.h

@@ -358,6 +358,9 @@ static Shortcut shortcuts[] = {
 	#if ISO14755_PATCH
 	{ TERMMOD,              XK_I,           iso14755,        {.i =  0} },
 	#endif // ISO14755_PATCH
+	#if INVERT_PATCH
+	{ TERMMOD,              XK_X,           invert,          { 0 } },
+	#endif // INVERT_PATCH
 };
 
 /*

patch/invert.c

@@ -0,0 +1,21 @@
+static int invertcolors = 0;
+
+void
+invert(const Arg *dummy)
+{
+	invertcolors = !invertcolors;
+	redraw();
+}
+
+Color
+invertedcolor(Color *clr)
+{
+	XRenderColor rc;
+	Color inverted;
+	rc.red = ~clr->color.red;
+	rc.green = ~clr->color.green;
+	rc.blue = ~clr->color.blue;
+	rc.alpha = clr->color.alpha;
+	XftColorAllocValue(xw.dpy, xw.vis, xw.cmap, &rc, &inverted);
+	return inverted;
+}

patch/invert.h

@@ -0,0 +1 @@
+static void invert(const Arg *);

patch/x_include.c

@@ -11,6 +11,9 @@
 #if FONT2_PATCH
 #include "font2.c"
 #endif
+#if INVERT_PATCH
+#include "invert.c"
+#endif
 #if KEYBOARDSELECT_PATCH
 #include "keyboardselect_x.c"
 #endif

patch/x_include.h

@@ -8,6 +8,9 @@
 #if FONT2_PATCH
 #include "font2.h"
 #endif
+#if INVERT_PATCH
+#include "invert.h"
+#endif
 #if KEYBOARDSELECT_PATCH
 #include "keyboardselect_x.h"
 #endif

patches.def.h

@@ -88,6 +88,13 @@
  */
 #define HIDECURSOR_PATCH 0
 
+/* This patch adds a keybinding that lets you invert the current colorscheme of st.
+ * This provides a simple way to temporarily switch to a light colorscheme if you use a dark
+ * colorscheme or visa-versa.
+ * https://st.suckless.org/patches/invert/
+ */
+#define INVERT_PATCH 0
+
 /* Pressing the default binding Ctrl+Shift-i will popup dmenu, asking you to enter a unicode
  * codepoint that will be converted to a glyph and then pushed to st.
  * https://st.suckless.org/patches/iso14755/

x.c

@@ -904,9 +904,18 @@ xsetcolorname(int x, const char *name)
 void
 xclear(int x1, int y1, int x2, int y2)
 {
+	#if INVERT_PATCH
+	Color c;
+	c = dc.col[IS_SET(MODE_REVERSE)? defaultfg : defaultbg];
+	if (invertcolors) {
+		c = invertedcolor(&c);
+	}
+	XftDrawRect(xw.draw, &c, x1, y1, x2-x1, y2-y1);
+	#else
 	XftDrawRect(xw.draw,
 			&dc.col[IS_SET(MODE_REVERSE)? defaultfg : defaultbg],
 			x1, y1, x2-x1, y2-y1);
+	#endif // INVERT_PATCH
 }
 
 void
@@ -1657,6 +1666,15 @@ xdrawglyphfontspecs(const XftGlyphFontSpec *specs, Glyph base, int len, int x, i
 	if (base.mode & ATTR_INVISIBLE)
 		fg = bg;
 
+	#if INVERT_PATCH
+	if (invertcolors) {
+		revfg = invertedcolor(fg);
+		revbg = invertedcolor(bg);
+		fg = &revfg;
+		bg = &revbg;
+	}
+	#endif // INVERT_PATCH
+
 	/* Intelligent cleaning up of the borders. */
 	#if ANYSIZE_PATCH
 	if (x == 0) {