shithub: puzzles

Info  •  Files  •  Log  •  Branches

David Nickerson reports odd behaviour involving a drag start point
persisting between separate mouse actions. Revamp all uses of the
ndragcoords field in an attempt to stamp that out: we now distinguish
between active drags (>0), a valid click but no drag yet (0), and a
totally invalid situation in which all mouse activity will be ignored
until the next fresh attempt (-1).

[originally from svn r9405]

--- a/pearl.c

+++ b/pearl.c

@@ -1717,7 +1717,8 @@

 struct game_ui {

     int *dragcoords;       /* list of (y*w+x) coords in drag so far */

-    int ndragcoords;       /* number of entries in dragcoords. 0 = no drag. */

+    int ndragcoords;       /* number of entries in dragcoords.

+                            * 0 = click but no drag yet. -1 = no drag at all */

     int clickx, clicky;    /* pixel position of initial click */

 };

@@ -1726,7 +1727,7 @@

     game_ui *ui = snew(game_ui);

     int sz = state->shared->sz;

-    ui->ndragcoords = 0;

+    ui->ndragcoords = -1;

     ui->dragcoords = snewn(sz, int);

     return ui;

@@ -1805,6 +1806,9 @@

     if (!INGRID(state, gx, gy))

         return;                        /* square is outside grid */

+    if (ui->ndragcoords < 0)

+        return;                        /* drag not in progress anyway */

+

     pos = gy * w + gx;

     lastpos = ui->dragcoords[ui->ndragcoords > 0 ? ui->ndragcoords-1 : 0];

@@ -1916,7 +1920,10 @@

     char tmpbuf[80];

     if (IS_MOUSE_DOWN(button)) {

-        if (!INGRID(state, gx, gy)) return NULL;

+        if (!INGRID(state, gx, gy)) {

+            ui->ndragcoords = -1;

+            return NULL;

+        }

         ui->clickx = x; ui->clicky = y;

         ui->dragcoords[0] = gy * w + gx;

@@ -1925,13 +1932,13 @@

         return "";

     }

-    if (button == LEFT_DRAG) {

+    if (button == LEFT_DRAG && ui->ndragcoords >= 0) {

         update_ui_drag(state, ui, gx, gy);

         return "";

     }

     if (IS_MOUSE_RELEASE(button)) {

-        if (ui->ndragcoords) {

+        if (ui->ndragcoords > 0) {

             /* End of a drag: process the cached line data. */

             int buflen = 0, bufsize = 256, tmplen;

             char *buf = NULL;

@@ -1957,10 +1964,10 @@

                 }

             }

-            ui->ndragcoords = 0;

+            ui->ndragcoords = -1;

             return buf ? buf : "";

-        } else {

+        } else if (ui->dragcoords == 0) {

             /* Click (or tiny drag). Work out which edge we were

              * closest to. */

             int cx, cy;

@@ -1967,6 +1974,8 @@

             int gx2, gy2, l1, l2, ismark = (button == RIGHT_RELEASE);

             char movec = ismark ? 'M' : 'F';

+            ui->ndragcoords = -1;

+

             /*

              * We process clicks based on the mouse-down location,

              * because that's more natural for a user to carefully

@@ -2321,7 +2330,7 @@

         flashing = DS_FLASH;

     memset(ds->draglines, 0, sz);

-    if (ui->dragcoords) {

+    if (ui->ndragcoords > 0) {

         int i, clearing = TRUE;

         for (i = 0; i < ui->ndragcoords - 1; i++) {

             int sx, sy, dx, dy, dir, oldstate, newstate;