new option -s 5: prefer file icon if size is equal

similar to default, but prefer equal-sized icon from file,
for better control over icon content: you can override
X11 property icon by file even if the former matches size exactly.
related: #170, 163.

doc/alttab.1

@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.9.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.9.1
-.TH "ALTTAB" "1" "July 2023" ""
+.TH "ALTTAB" "1" "May 2024" ""
 .SH "NAME"
 \fBalttab\fR \- the task switcher
 .SH "SYNOPSIS"
@@ -179,7 +179,7 @@ resource: alttab\.icon\.source
 .br
 default: 2
 .IP
-Source of icons\. \fINUMBER\fR must be between 0 and 4:
+Source of icons\. \fINUMBER\fR must be between 0 and 5:
 .IP
 \fI0\fR: Use icons from X11 window attributes only\.
 .IP
@@ -208,6 +208,8 @@ Also, alttab scans for icons in legacy directories without freedesktop directory
 \fI3\fR: Use icons from files only\.
 .IP
 \fI4\fR: Don't draw icons\.
+.IP
+\fI5\fR: Prefer icon from X11 window attributes when it matches requested size better\.
 .TP
 \fB\-theme\fR \fIname\fR
 resource: alttab\.theme

doc/alttab.1.ronn

@@ -218,7 +218,7 @@ Most command line options have corresponding X resource, see doc/alttab.ad for e
     resource: alttab.icon.source  
     default: 2
 
-    Source of icons. <NUMBER> must be between 0 and 4:
+    Source of icons. <NUMBER> must be between 0 and 5:
 
       <0>: Use icons from X11 window attributes only.
 
@@ -249,6 +249,8 @@ Most command line options have corresponding X resource, see doc/alttab.ad for e
 
       <4>: Don't draw icons.
 
+      <5>: Prefer icon from X11 window attributes when it matches requested size better.
+
   * `-theme` <name>:
     resource: alttab.theme  
     default: <hicolor>

src/alttab.h

@@ -187,7 +187,8 @@ typedef struct {
 #define ISRC_SIZE       2
 #define ISRC_FILES      3
 #define ISRC_NONE       4
-#define ISRC_MAX        4
+#define ISRC_SIZE2      5
+#define ISRC_MAX        5
 #define ISRC_DEFAULT    ISRC_SIZE
     int option_iconSrc;
     char *option_theme;

src/icon.c

@@ -412,7 +412,7 @@ int inspectIconMeta(FTSENT * pe)
         // new candidate: ix, iy
         // best value: g.option_iconW, H
         // should we replace the icon?
-        if (iconMatchBetter(ix, iy, ic->src_w, ic->src_h)) {
+        if (iconMatchBetter(ix, iy, ic->src_w, ic->src_h, false)) {
             strncpy(ic->src_path, pe->fts_path, MAXICONPATHLEN-1);
             ic->src_w = ix;
             ic->src_h = iy;
@@ -506,13 +506,16 @@ icon_t *lookupIcon(char *app)
 //
 // check if new width/height better match icon size option
 // assuming square icons
+// if equal_prefer_new=true and sizes are equal, then prefer new icon
 //
-bool iconMatchBetter(int new_w, int new_h, int old_w, int old_h)
+bool iconMatchBetter(int new_w, int new_h, int old_w, int old_h, bool equal_prefer_new)
 {
     int hasdiff, newdiff;
 
     hasdiff = old_h - g.option_iconH;
     newdiff = new_h - g.option_iconH;
+    if (hasdiff == newdiff && equal_prefer_new)
+        return true;
     return
         (hasdiff >= 0) ? ((newdiff < 0) ? false : ((newdiff <
                                                     hasdiff) ? true : false)

src/icon.h

@@ -68,7 +68,7 @@ int loadIconContentPNG(icon_t * ic);
 int loadIconContentXPM(icon_t * ic);
 int loadIconContent(icon_t * ic);   // update drawable
 icon_t *lookupIcon(char *app);  // search app icon in hash
-bool iconMatchBetter(int new_w, int new_h, int old_w, int old_h);
+bool iconMatchBetter(int new_w, int new_h, int old_w, int old_h, bool equal_prefer_new);
 void deleteIconHash(icon_t **ihash);
 
 #endif

src/win.c

@@ -224,7 +224,7 @@ int addIconFromProperty(WindowInfo * wi)
             n += w*h;
             continue;
         }
-        if (best == 0 || iconMatchBetter(w, h, best_w, best_h)) {
+        if (best == 0 || iconMatchBetter(w, h, best_w, best_h, false)) {
             best = n;
         }
         n += w*h;
@@ -343,11 +343,20 @@ int addIconFromFiles(WindowInfo * wi)
             s = tryclass;
             while ((s = strchr(s, '/')) != NULL) *s++ = '_';
             ic = lookupIcon(tryclass);
-            if (ic &&
-                (g.option_iconSrc != ISRC_SIZE
-                 || iconMatchBetter(ic->src_w, ic->src_h,
-                                    wi->icon_w, wi->icon_h))
-                ) {
+            if (ic && (
+                (g.option_iconSrc != ISRC_SIZE 
+                        && g.option_iconSrc != ISRC_SIZE2)
+                 || (g.option_iconSrc == ISRC_SIZE 
+                        && iconMatchBetter(
+                                    ic->src_w, ic->src_h,
+                                    wi->icon_w, wi->icon_h,
+                                    false))
+                 || (g.option_iconSrc == ISRC_SIZE2 
+                        && iconMatchBetter(
+                                    ic->src_w, ic->src_h,
+                                    wi->icon_w, wi->icon_h,
+                                    true))
+                )) {
                 msg(0, "using file icon for %s\n", tryclass);
                 if (ic->drawable == None) {
                     msg(1, "loading content for %s\n", ic->app);
@@ -446,7 +455,7 @@ int addWindowInfo(Window win, int reclevel, int wm_id, unsigned long desktop,
             icon_in_x = addIconFromHints(&(WI));
     }
     if ((opt == ISRC_FALLBACK && !icon_in_x) ||
-        opt == ISRC_SIZE || opt == ISRC_FILES)
+        opt == ISRC_SIZE || opt == ISRC_SIZE2 || opt == ISRC_FILES)
         addIconFromFiles(&(WI));
 
     // extract icon width/height/depth