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authorpeter1138 <peter1138@openttd.org>2007-06-25 21:50:36 +0000
committerpeter1138 <peter1138@openttd.org>2007-06-25 21:50:36 +0000
commit217765fc0bdd036e1ded296fcbf77ab3c9f98f05 (patch)
treeff67e9de14b4d2284cb136d460aec0951ae77ce3 /src
parent36945fd6286d867c9f6d93f3c54a9d4927f2ba86 (diff)
downloadopenttd-217765fc0bdd036e1ded296fcbf77ab3c9f98f05.tar.xz
(svn r10334) -Fix [FS#937]: with smooth scrolling enabled, the viewport destination was not clamped to the map
Diffstat (limited to 'src')
-rw-r--r--src/viewport.cpp64
1 files changed, 33 insertions, 31 deletions
diff --git a/src/viewport.cpp b/src/viewport.cpp
index 2bac971c2..935627cfa 100644
--- a/src/viewport.cpp
+++ b/src/viewport.cpp
@@ -1361,6 +1361,30 @@ void DrawWindowViewport(const Window *w)
dpi->top -= w->top;
}
+static inline void ClampViewportToMap(const ViewPort *vp, int &x, int &y)
+{
+ /* Centre of the viewport is hot spot */
+ x += vp->virtual_width / 2;
+ y += vp->virtual_height / 2;
+
+ /* Convert viewport coordinates to map coordinates
+ * Calculation is scaled by 4 to avoid rounding errors */
+ int vx = -x + y * 2;
+ int vy = x + y * 2;
+
+ /* clamp to size of map */
+ vx = clamp(vx, 0, MapMaxX() * TILE_SIZE * 4);
+ vy = clamp(vy, 0, MapMaxY() * TILE_SIZE * 4);
+
+ /* Convert map coordinates to viewport coordinates */
+ x = (-vx + vy) / 2;
+ y = ( vx + vy) / 4;
+
+ /* Remove centreing */
+ x -= vp->virtual_width / 2;
+ y -= vp->virtual_height / 2;
+}
+
void UpdateViewportPosition(Window *w)
{
const ViewPort *vp = w->viewport;
@@ -1371,47 +1395,25 @@ void UpdateViewportPosition(Window *w)
SetViewportPosition(w, pt.x, pt.y);
} else {
- int x;
- int y;
- int vx;
- int vy;
-
- /* Center of the viewport is hot spot */
- x = WP(w,vp_d).scrollpos_x + vp->virtual_width / 2;
- y = WP(w,vp_d).scrollpos_y + vp->virtual_height / 2;
+ /* Ensure the destination location is within the map */
+ ClampViewportToMap(vp, WP(w, vp_d).dest_scrollpos_x, WP(w, vp_d).dest_scrollpos_y);
- int dest_x = WP(w,vp_d).dest_scrollpos_x + vp->virtual_width / 2;
- int dest_y = WP(w,vp_d).dest_scrollpos_y + vp->virtual_height / 2;
-
- int delta_x = dest_x - x;
- int delta_y = dest_y - y;
+ int delta_x = WP(w, vp_d).dest_scrollpos_x - WP(w, vp_d).scrollpos_x;
+ int delta_y = WP(w, vp_d).dest_scrollpos_y - WP(w, vp_d).scrollpos_y;
if (delta_x != 0 || delta_y != 0) {
if (_patches.smooth_scroll) {
int max_scroll = ScaleByMapSize1D(512);
/* Not at our desired positon yet... */
- x += clamp(delta_x / 8, -max_scroll, max_scroll);
- y += clamp(delta_y / 8, -max_scroll, max_scroll);
+ WP(w, vp_d).scrollpos_x += clamp(delta_x / 4, -max_scroll, max_scroll);
+ WP(w, vp_d).scrollpos_y += clamp(delta_y / 4, -max_scroll, max_scroll);
} else {
- x = dest_x;
- y = dest_y;
+ WP(w, vp_d).scrollpos_x = WP(w, vp_d).dest_scrollpos_x;
+ WP(w, vp_d).scrollpos_y = WP(w, vp_d).dest_scrollpos_y;
}
}
- /* Convert viewport coordinates to map coordinates
- * Calculation is scaled by 4 to avoid rounding errors */
- vx = -x + y * 2;
- vy = x + y * 2;
- /* clamp to size of map */
- vx = clamp(vx, 0 * 4, MapMaxX() * TILE_SIZE * 4);
- vy = clamp(vy, 0 * 4, MapMaxY() * TILE_SIZE * 4);
- /* Convert map coordinates to viewport coordinates */
- x = (-vx + vy) / 2;
- y = ( vx + vy) / 4;
- /* Set position */
- WP(w, vp_d).scrollpos_x = x - vp->virtual_width / 2;
- WP(w, vp_d).scrollpos_y = y - vp->virtual_height / 2;
-
+ ClampViewportToMap(vp, WP(w, vp_d).scrollpos_x, WP(w, vp_d).scrollpos_y);
SetViewportPosition(w, WP(w, vp_d).scrollpos_x, WP(w, vp_d).scrollpos_y);
}
}