adding color picking on iOS

engine/app.cpp

@@ -88,7 +88,8 @@ void App::init()
 
     LOG("Screen Resolution: %dx%d", (int)width, (int)height);
 
-    zoom = ceilf(width / 2000.f);
+    //zoom = ceilf(width / 2000.f);
+    //zoom = 2;
     
 #ifdef __IOS__
     NSArray* paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
@@ -119,6 +120,9 @@ void App::update(float dt)
     // update offscreen stuff
     if (canvas && canvas->m_canvas)
         canvas->m_canvas->stroke_draw();
+    
+    if (!redraw)
+        return;
 
     //glClearColor(.1f, .1f, .1f, 1.f);
     //glViewport(0, 0, (GLsizei)width, (GLsizei)height);
@@ -129,6 +133,13 @@ void App::update(float dt)
 #endif
     if (auto* main = layout[main_id])
         main->update(width, height, zoom);
+    
+    static glm::vec4 color_button_normal{.1, .1, .1, 1};
+    static glm::vec4 color_button_hlight{ 1, .0, .0, 1};
+    CanvasModePen* mode = (CanvasModePen*)canvas->m_canvas->modes[(int)Canvas::kCanvasMode::Draw][0];
+    layout[main_id]->find<NodeButton>("btn-pick")->set_color(
+         mode->m_picking ? color_button_hlight : color_button_normal);
+
 
     auto observer = [this](Node* n)
     {
@@ -145,7 +156,9 @@ void App::update(float dt)
     if (auto* main = layout[main_id])
         main->watch(observer);
     //msgbox->watch(observer);
-    glDisable(GL_SCISSOR_TEST); 
+    glDisable(GL_SCISSOR_TEST);
+    
+    redraw = false;
 }