improve sliders and remove slider cursor, fix stroke preview

engine/app.cpp

@@ -318,16 +318,16 @@ void App::init()
     glEnable(GL_DEBUG_OUTPUT); 
 #endif
 
-    initShaders();
-    initAssets();
-    initLayout();
-
     glEnable(GL_TEXTURE_2D);
     glDisable(GL_DEPTH_TEST);
 
     glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
     glBlendEquation(GL_FUNC_ADD);
 
+    initShaders();
+    initAssets();
+    initLayout();
+
     //int n;
     //glGetIntegerv(GL_NUM_EXTENSIONS, &n);
     //for (int i = 0; i < n; i++)
@@ -351,7 +351,9 @@ void App::update(float dt)
     glViewport(0, 0, (GLsizei)width, (GLsizei)height);
     glClear(GL_COLOR_BUFFER_BIT);
 
-    //layout.reload();
+#ifndef __ANDROID__
+    layout.reload();
+#endif
     if (auto* main = layout[main_id])
         main->update(width, height, zoom);