From d74976944c982027746d2a99a3e5a15e034b4b99 Mon Sep 17 00:00:00 2001
From: Marko Lindqvist <cazfi74@gmail.com>
Date: Sat, 8 Apr 2023 21:47:25 +0300
Subject: [PATCH 42/42] Zoom: Add support for gui-specific zoom steps

See osdn #47813

Signed-off-by: Marko Lindqvist <cazfi74@gmail.com>
---
 client/zoom.c | 30 ++++++++++++++++++++++++------
 client/zoom.h |  3 ++-
 2 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/client/zoom.c b/client/zoom.c
index 0e79443aa4..c94d0a320b 100644
--- a/client/zoom.c
+++ b/client/zoom.c
@@ -24,7 +24,7 @@
 float map_zoom = 1.0;
 bool zoom_enabled = FALSE;
 
-static float zoom_steps[] = {
+static float default_zoom_steps[] = {
 #ifdef EXP_ZOOM_LEVELS
   -1.0, 0.13, 0.25, 0.5, 0.75, 1.0, 1.25, 1.5, 2.0, 2.5, 3.0, 4.0, -1.0
 #else
@@ -32,6 +32,8 @@ static float zoom_steps[] = {
 #endif /* EXP_ZOOM_LEVELS */
 };
 
+static float *zoom_steps = default_zoom_steps;
+
 static struct zoom_data
 {
   bool active;
@@ -63,6 +65,20 @@ void zoom_1_0(void)
   map_canvas_resized(mapview.width, mapview.height);
 }
 
+/**********************************************************************//**
+  Set list of zoom steps that the system uses.
+  The list is not copied - caller is expected to maintain it.
+  First and last value must be -1.0
+**************************************************************************/
+void zoom_set_steps(float *steps)
+{
+  if (steps == NULL) {
+    zoom_steps = default_zoom_steps;
+  } else {
+    zoom_steps = steps;
+  }
+}
+
 /**********************************************************************//**
   Zoom level one step up
 **************************************************************************/
@@ -75,7 +91,7 @@ void zoom_step_up(void)
   for (i = 1 ;
        zoom_steps[i] < map_zoom * 1.05 && zoom_steps[i] > 0.0 ;
        i++ ) {
-    /* empty */
+    /* Empty */
   }
 
   if (zoom_steps[i] > 0.0) {
@@ -96,12 +112,14 @@ void zoom_step_down(void)
 
   /* Even if above previous step, close enough is considered to be in
    * previous step so that change is not miniscule */
-  for (i = ARRAY_SIZE(zoom_steps) - 2 ;
-       zoom_steps[i] * 1.05 > map_zoom && zoom_steps[i] > 0.0 ;
-       i-- ) {
-    /* empty */
+  for (i = 1;
+       zoom_steps[i] < map_zoom * 1.05 && zoom_steps[i] > 0.0 ;
+       i++) {
   }
 
+  /* Get back, and below */
+  i = MAX(i - 2, 1);
+
   if (zoom_steps[i] > 0.0) {
     if (zoom_steps[i] > 0.99 && zoom_steps[i] < 1.01) {
       zoom_1_0();
diff --git a/client/zoom.h b/client/zoom.h
index 5815554775..d5b8f77078 100644
--- a/client/zoom.h
+++ b/client/zoom.h
@@ -1,4 +1,4 @@
-/********************************************************************** 
+/***********************************************************************
  Freeciv - Copyright (C) 1996 - A Kjeldberg, L Gregersen, P Unold
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -19,6 +19,7 @@ extern "C" {
 
 void zoom_set(float new_zoom);
 void zoom_1_0(void);
+void zoom_set_steps(float *steps);
 
 #define zoom_get_level() map_zoom
 #define zoom_is_enabled() zoom_enabled
-- 
2.39.2