diff --git a/MobileGL/MG_Impl/EGLImpl/EGLForVulkan/EGLForVulkan.cpp b/MobileGL/MG_Impl/EGLImpl/EGLForVulkan/EGLForVulkan.cpp
index 5e082398..f221cf1d 100644
--- a/MobileGL/MG_Impl/EGLImpl/EGLForVulkan/EGLForVulkan.cpp
+++ b/MobileGL/MG_Impl/EGLImpl/EGLForVulkan/EGLForVulkan.cpp
@@ -17,9 +17,10 @@ namespace MobileGL {
         // TODO: complete EGL impl for Vulkan
 
         const char* demoFS = R"(#version 460
+        layout(location = 0) in vec3 fragColor;
         layout(location = 0) out vec4 outColor;
         void main() {
-            outColor = vec4(0.0, 1.0, 0.0, 1.0);
+            outColor = vec4(fragColor, 1.0);
         }
 )";
         const char* demoVS = R"(#version 460
@@ -27,8 +28,8 @@ namespace MobileGL {
         vec2 positions[3] = vec2[](vec2(0.0, -0.5), vec2(0.5, 0.5), vec2(-0.5, 0.5));
         vec3 colors[3] = vec3[](vec3(1.0, 0.0, 0.0), vec3(0.0, 1.0, 0.0), vec3(0.0, 0.0, 1.0));
         void main() {
-            gl_Position = vec4(positions[gl_VertexIndex], 0.0, 1.0);
-            fragColor = colors[gl_VertexIndex];
+            gl_Position = vec4(positions[gl_VertexID], 0.0, 1.0);
+            fragColor = colors[gl_VertexID];
         }
 )";
         void PrepareDemoRes() {