diff --git a/example/Vulkan/first_triangle.cpp b/example/Vulkan/first_triangle.cpp
index 5b671e6d..9784cc56 100644
--- a/example/Vulkan/first_triangle.cpp
+++ b/example/Vulkan/first_triangle.cpp
@@ -98,7 +98,12 @@ private:
 
     bool InitAutoMaterial()
     {
-        AutoDelete<MaterialCreateInfo> mci=mtl::CreateVertexColor2D(mtl::CoordinateSystem2D::NDC);
+        mtl::Material2DConfig cfg;
+
+        cfg.coordinate_system=mtl::CoordinateSystem2D::NDC;
+        cfg.local_to_world=false;
+
+        AutoDelete<MaterialCreateInfo> mci=mtl::CreateVertexColor2D(&cfg);
 
         material_instance=db->CreateMaterialInstance(mci,&vil_config);
 
diff --git a/example/Vulkan/second_triangle.cpp b/example/Vulkan/second_triangle.cpp
index 351d3e25..3b7d5c32 100644
--- a/example/Vulkan/second_triangle.cpp
+++ b/example/Vulkan/second_triangle.cpp
@@ -45,15 +45,17 @@ private:
 
     bool InitMaterial()
     {
-        AutoDelete<MaterialCreateInfo> mci;
+        mtl::Material2DConfig cfg;
 
 #ifdef USE_ZERO2ONE_COORD
-        mci=mtl::CreateVertexColor2D(mtl::CoordinateSystem2D::ZeroToOne);
+        cfg.coordinate_system=mtl::CoordinateSystem2D::ZeroToOne;
 #else
-        mci=mtl::CreateVertexColor2D(mtl::CoordinateSystem2D::Ortho);
+        cfg.coordinate_system=mtl::CoordinateSystem2D::Ortho;
 #endif//USE_ZERO2ONE_COORD
 
-        //material_instance=db->CreateMaterialInstance(OS_TEXT("res/material/VertexColor2D"));
+        cfg.local_to_world=false;
+
+        AutoDelete<MaterialCreateInfo> mci=mtl::CreateVertexColor2D(&cfg);
 
         material_instance=db->CreateMaterialInstance(mci);
 
diff --git a/example/common/VulkanAppFramework.h b/example/common/VulkanAppFramework.h
index c2ec093b..dae9020b 100644
--- a/example/common/VulkanAppFramework.h
+++ b/example/common/VulkanAppFramework.h
@@ -205,7 +205,7 @@ public:
                 cb->BindDescriptorSets(ri);
                 cb->BindVBO(ri);
 
-                    if (vid->index_buffer)
+                    if (vid->index_buffer->buffer)
                         cb->DrawIndexed(vid->index_buffer->buffer->GetCount());
                     else
                         cb->Draw(vid->vertex_count);