18-ibl: Fix widgets id conflict (#3424)

examples/18-ibl/ibl.cpp

@@ -636,7 +636,7 @@ public:
 				ImGui::Separator();
 				ImGui::Text("Workflow:");
 				ImGui::Indent();
-				ImGui::RadioButton("Metalness", &m_settings.m_metalOrSpec, 0);
+				ImGui::RadioButton("Metalness##Button", &m_settings.m_metalOrSpec, 0);
 				ImGui::RadioButton("Specular", &m_settings.m_metalOrSpec, 1);
 				ImGui::Unindent();
 
@@ -645,7 +645,7 @@ public:
 				ImGui::Indent();
 				ImGui::PushItemWidth(130.0f);
 				ImGui::SliderFloat("Glossiness", &m_settings.m_glossiness, 0.0f, 1.0f);
-				ImGui::SliderFloat(0 == m_settings.m_metalOrSpec ? "Metalness" : "Diffuse - Specular", &m_settings.m_reflectivity, 0.0f, 1.0f);
+				ImGui::SliderFloat(0 == m_settings.m_metalOrSpec ? "Metalness##Slider" : "Diffuse - Specular", &m_settings.m_reflectivity, 0.0f, 1.0f);
 				ImGui::PopItemWidth();
 				ImGui::Unindent();
 			}