Remove ARGB as a window mode

Instead use win_has_alpha to check for alpha channel, window mode is
reserved for determine if the window is possibly transparent.

Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>

src/c2.c

@@ -26,6 +26,7 @@
 #endif
 
 #include "common.h"
+#include "win.h"
 #include "c2.h"
 
 #define C2_MAX_LEVELS 10
@@ -1398,7 +1399,7 @@ c2_match_once_leaf(session_t *ps, win *w, const c2_l_t *pleaf,
             case C2_L_PBDW:     tgt = w->g.border_width;        break;
             case C2_L_PFULLSCREEN: tgt = win_is_fullscreen(ps, w); break;
             case C2_L_POVREDIR: tgt = w->a.override_redirect;   break;
-            case C2_L_PARGB:    tgt = (WMODE_ARGB == w->mode);  break;
+            case C2_L_PARGB:    tgt = win_has_alpha(w);         break;
             case C2_L_PFOCUSED: tgt = win_is_focused_real(ps, w); break;
             case C2_L_PWMWIN:   tgt = w->wmwin;                 break;
             case C2_L_PBSHAPED: tgt = w->bounding_shaped;       break;

src/common.h

@@ -273,9 +273,9 @@ typedef struct {
 
 /// Enumeration type of window painting mode.
 typedef enum {
-  WMODE_TRANS,
-  WMODE_SOLID,
-  WMODE_ARGB
+  WMODE_TRANS, // The window body is (potentially) transparent
+  WMODE_FRAME_TRANS, // The window body is opaque, but the frame is not
+  WMODE_SOLID, // The window is opaque including the frame
 } winmode_t;
 
 /// Structure representing needed window updates.

src/compton.c

@@ -1511,7 +1511,7 @@ win_paint_win(session_t *ps, win *w, XserverRegion reg_paint,
           newpict, 0, 0, 0, 0, 0, 0, wid, hei);
       // We use an extra PictOpInReverse operation to get correct pixel
       // alpha. There could be a better solution.
-      if (WMODE_ARGB == w->mode)
+      if (win_has_alpha(w))
         xcb_render_composite(c, XCB_RENDER_PICT_OP_IN_REVERSE, pict, None,
             newpict, 0, 0, 0, 0, 0, 0, wid, hei);
       pict = newpict;

src/compton.h

@@ -497,13 +497,14 @@ find_win_all(session_t *ps, const Window wid) {
   render_(ps, x, y, dx, dy, wid, hei, opacity, argb, neg, pict, ptex, reg_paint, pcache_reg)
 #endif
 
+bool win_has_alpha(win *);
 static inline void
 win_render(session_t *ps, win *w, int x, int y, int wid, int hei,
     double opacity, XserverRegion reg_paint, const reg_data_t *pcache_reg,
     xcb_render_picture_t pict) {
   const int dx = (w ? w->g.x: 0) + x;
   const int dy = (w ? w->g.y: 0) + y;
-  const bool argb = (w && (WMODE_ARGB == w->mode || ps->o.force_win_blend));
+  const bool argb = (w && (win_has_alpha(w) || ps->o.force_win_blend));
   const bool neg = (w && w->invert_color);
 
   render(ps, x, y, dx, dy, wid, hei, opacity, argb, neg,

src/win.c

@@ -281,19 +281,21 @@ bool wid_get_opacity_prop(session_t *ps, Window wid, opacity_t def,
   return ret;
 }
 
+// XXX should distinguish between frame has alpha and window body has alpha
+bool win_has_alpha(win *w) {
+  return w->pictfmt &&
+    w->pictfmt->type == XCB_RENDER_PICT_TYPE_DIRECT &&
+    w->pictfmt->direct.alpha_mask;
+}
+
 void win_determine_mode(session_t *ps, win *w) {
-  winmode_t mode = WMODE_SOLID;
-
-  if (w->pictfmt && w->pictfmt->type == XCB_RENDER_PICT_TYPE_DIRECT &&
-      w->pictfmt->direct.alpha_mask) {
-    mode = WMODE_ARGB;
-  } else if (w->opacity != OPAQUE) {
-    mode = WMODE_TRANS;
+  if (win_has_alpha(w) || w->opacity != OPAQUE) {
+    w->mode = WMODE_TRANS;
+  } else if (w->frame_opacity) {
+    w->mode = WMODE_FRAME_TRANS;
   } else {
-    mode = WMODE_SOLID;
+    w->mode = WMODE_SOLID;
   }
-
-  w->mode = mode;
 }
 
 /**
@@ -375,7 +377,7 @@ void win_determine_fade(session_t *ps, win *w) {
   else if (ps->o.no_fading_openclose && w->in_openclose)
     w->fade_last = w->fade = false;
   else if (ps->o.no_fading_destroyed_argb && w->destroyed &&
-           WMODE_ARGB == w->mode && w->client_win && w->client_win != w->id) {
+           win_has_alpha(w) && w->client_win && w->client_win != w->id) {
     w->fade_last = w->fade = false;
   }
   // Ignore other possible causes of fading state changes after window

src/win.h

@@ -95,3 +95,6 @@ static inline Window
 win_get_leader(session_t *ps, win *w) {
   return win_get_leader_raw(ps, w, 0);
 }
+
+/// check if window has ARGB visual
+bool win_has_alpha(win *w);

src/x.c

@@ -1,3 +1,5 @@
+#include <stdbool.h>
+
 #include <X11/Xlib.h>
 #include <xcb/xcb_renderutil.h>
 
@@ -96,16 +98,18 @@ bool wid_get_text_prop(session_t *ps, Window wid, Atom prop,
 }
 
 static inline void x_get_server_pictfmts(session_t *ps) {
-    xcb_connection_t *c = XGetXCBConnection(ps->dpy);
-    xcb_generic_error_t *e = NULL;
-    // Get window picture format
-    ps->pictfmts =
-      xcb_render_query_pict_formats_reply(c,
-          xcb_render_query_pict_formats(c), &e);
-    if (e || !ps->pictfmts) {
-      printf_errf("(): failed to get pict formats\n");
-      abort();
-    }
+  if (ps->pictfmts)
+    return;
+  xcb_connection_t *c = XGetXCBConnection(ps->dpy);
+  xcb_generic_error_t *e = NULL;
+  // Get window picture format
+  ps->pictfmts =
+    xcb_render_query_pict_formats_reply(c,
+        xcb_render_query_pict_formats(c), &e);
+  if (e || !ps->pictfmts) {
+    printf_errf("(): failed to get pict formats\n");
+    abort();
+  }
 }
 
 xcb_render_pictforminfo_t *x_get_pictform_for_visual(session_t *ps, xcb_visualid_t visual) {
@@ -116,8 +120,9 @@ xcb_render_pictforminfo_t *x_get_pictform_for_visual(session_t *ps, xcb_visualid
   for(xcb_render_pictforminfo_iterator_t i =
       xcb_render_query_pict_formats_formats_iterator(ps->pictfmts); i.rem;
       xcb_render_pictforminfo_next(&i)) {
-    if (i.data->id == pv->format)
+    if (i.data->id == pv->format) {
       return i.data;
+    }
   }
   return NULL;
 }

src/x.h

@@ -64,5 +64,5 @@ __attribute__((nonnull(1)));
  */
 xcb_render_picture_t
 x_create_picture(session_t *ps, int wid, int hei,
-    xcb_render_pictforminfo_t *pictfmt, unsigned long valuemask,
-    const xcb_render_create_picture_value_list_t *attr);
+  xcb_render_pictforminfo_t *pictfmt, unsigned long valuemask,
+  const xcb_render_create_picture_value_list_t *attr);