open presets from the brush preview, fix scrollbar redraw

src/node_panel_stroke.cpp

@@ -252,7 +252,7 @@ void NodePanelStroke::init_controls()
     m_presets_popup->create();
     m_presets_popup->loaded();
     m_presets_popup->SetPositioning(YGPositionTypeAbsolute);
-    m_presets_popup->SetSize(300, 400);
+    m_presets_popup->SetSize(YGUndefined, 400);
     m_presets_popup->m_mouse_ignore = false;
     m_presets_popup->m_flood_events = true;
     m_presets_popup->m_capture_children = false;
@@ -272,7 +272,7 @@ void NodePanelStroke::init_controls()
 
     // BRUSH PRESETS
 
-    m_preset_button = find<NodeButton>("preset-button");
+    m_preset_button = find<NodeButtonCustom>("preset-button");
     m_preset_button->on_click = [this](Node*) {
         auto screen = root()->m_size;
         glm::vec2 pos = m_preset_button->m_pos + glm::vec2(m_preset_button->m_size.x, 0);
@@ -283,7 +283,7 @@ void NodePanelStroke::init_controls()
         tick->SetPosition(pos.x, pos.y + (m_preset_button->m_size.y - 32) * 0.5f);
         tick->set_image("data/ui/popup-tick.png");
         float hh = m_presets_popup->m_container->m_children.size() > 10 ? App::I.height / App::I.zoom * .75f : 400.f;
-        m_presets_popup->SetSize(300, glm::max(hh, 400.f));
+        m_presets_popup->SetHeight(glm::max(hh, 400.f));
         root()->update();
         if ((pos.y + m_presets_popup->m_size.y) > screen.y) 
             pos.y = screen.y - m_presets_popup->m_size.y;

src/node_panel_stroke.h

@@ -48,7 +48,7 @@ public:
     NodeImage* m_brush_thumb;
     NodeImage* m_dual_brush_thumb;
     NodeImage* m_pattern_thumb;
-    NodeButton* m_preset_button;
+    NodeButtonCustom* m_preset_button;
 
     NodeCheckBox* m_tip_invert;
     NodeCheckBox* m_tip_flipx;

src/node_scroll.cpp

@@ -34,7 +34,10 @@ void NodeScroll::on_tick(float dt)
     float sz = m_size.y - (pad[0] + pad[2]);
     float new_pad = rect.w == 0 || rect.w <= sz ? 5 : 35;
     if (pad[1] != new_pad)
+    {
         YGNodeStyleSetPadding(y_node, YGEdgeRight, new_pad);
+        app_redraw();
+    }
 }
 
 void NodeScroll::draw()