zoom toward mouse cursor on wheel scroll

1 files changed, 16 insertions, 2 deletions

diff --git a/src/editor/view2d.cpp b/src/editor/view2d.cpp
index 1445cfc..faff736 100644
--- a/src/editor/view2d.cpp
+++ b/src/editor/view2d.cpp
@@ -727,12 +727,26 @@ void gui_editor_2dview_input_scroll( GUI_EDITOR_2DVIEW* view ) {
   U8 scroll = gui_mbutton_down( GUI_MBTNSCROLL );
   gui_capture_scroll();
 
+  F32 zoom_factor = 1.f;
   if( scroll == (U8)-1 && view->scale > 0.5f ) {
-    view->scale *= 0.75f;
+    zoom_factor = 0.75f;
   }
   else if( scroll == 1 && view->scale < 16.f ) {
-    view->scale *= 1.25f;
+    zoom_factor = 1.25f;
   }
+
+  if( zoom_factor == 1.f )
+    return;
+
+  I32 mx, my;
+  gui_cursor_pos( &mx, &my );
+  VEC2 world_before = gui_editor_2dview_screen_to_world( view, mx, my );
+
+  view->scale *= zoom_factor;
+
+  VEC2 world_after = gui_editor_2dview_screen_to_world( view, mx, my );
+  view->posx += world_before.x - world_after.x;
+  view->posy += world_before.y - world_after.y;
 }
 
 void gui_editor_2dview_input_tool_wall( GUI_EDITOR_2DVIEW* view ) {