diff --git a/scwx-qt/gl/geo_line.vert b/scwx-qt/gl/geo_line.vert
index 4fea6910..ea7d6351 100644
--- a/scwx-qt/gl/geo_line.vert
+++ b/scwx-qt/gl/geo_line.vert
@@ -15,8 +15,8 @@ uniform mat4 uMVPMatrix;
 uniform mat4 uMapMatrix;
 uniform vec2 uMapScreenCoord;
 
-flat out vec2 texCoord;
-flat out vec4 modulate;
+smooth out vec2 texCoord;
+flat   out vec4 modulate;
 
 vec2 latLngToScreenCoordinate(in vec2 latLng)
 {
diff --git a/scwx-qt/gl/texture2d.frag b/scwx-qt/gl/texture2d.frag
index 3a41c720..16ab8960 100644
--- a/scwx-qt/gl/texture2d.frag
+++ b/scwx-qt/gl/texture2d.frag
@@ -5,8 +5,8 @@ precision mediump float;
 
 uniform sampler2D uTexture;
 
-flat in vec2 texCoord;
-flat in vec4 modulate;
+smooth in vec2 texCoord;
+flat   in vec4 modulate;
 
 layout (location = 0) out vec4 fragColor;