diff --git a/examples/shader/image.go b/examples/shader/image.go
index 0c05994bc..0dcd1620d 100644
--- a/examples/shader/image.go
+++ b/examples/shader/image.go
@@ -16,6 +16,8 @@
 
 package main
 
+var Time float
+var Cursor vec2
 var Image texture2d
 
 func Vertex(position vec2, texCoord vec2, color vec4) (vec4, vec2) {
@@ -27,7 +29,7 @@ func Vertex(position vec2, texCoord vec2, color vec4) (vec4, vec2) {
 	) * vec4(position, 0, 1), texCoord
 }
 
-func Fragment(position vec4, tex vec2) vec4 {
+func Fragment(position vec4, texCoord vec2) vec4 {
 	// TODO: Instead of using texture2D directly, define and use special functions for Ebiten images.
-	return texture2D(Image, tex)
+	return texture2D(Image, texCoord)
 }
diff --git a/examples/shader/image_go.go b/examples/shader/image_go.go
index 2b7ca81a6..74baac79b 100644
--- a/examples/shader/image_go.go
+++ b/examples/shader/image_go.go
@@ -3,4 +3,4 @@
 
 package main
 
-var image_go = []byte("// Copyright 2020 The Ebiten Authors\n//\n// Licensed under the Apache License, Version 2.0 (the \"License\");\n// you may not use this file except in compliance with the License.\n// You may obtain a copy of the License at\n//\n//     http://www.apache.org/licenses/LICENSE-2.0\n//\n// Unless required by applicable law or agreed to in writing, software\n// distributed under the License is distributed on an \"AS IS\" BASIS,\n// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\n// See the License for the specific language governing permissions and\n// limitations under the License.\n\n// +build ignore\n\npackage main\n\nvar Image texture2d\n\nfunc Vertex(position vec2, texCoord vec2, color vec4) (vec4, vec2) {\n\treturn mat4(\n\t\t2/viewportSize().x, 0, 0, 0,\n\t\t0, 2/viewportSize().y, 0, 0,\n\t\t0, 0, 1, 0,\n\t\t-1, -1, 0, 1,\n\t) * vec4(position, 0, 1), texCoord\n}\n\nfunc Fragment(position vec4, tex vec2) vec4 {\n\t// TODO: Instead of using texture2D directly, define and use special functions for Ebiten images.\n\treturn texture2D(Image, tex)\n}\n")
+var image_go = []byte("// Copyright 2020 The Ebiten Authors\n//\n// Licensed under the Apache License, Version 2.0 (the \"License\");\n// you may not use this file except in compliance with the License.\n// You may obtain a copy of the License at\n//\n//     http://www.apache.org/licenses/LICENSE-2.0\n//\n// Unless required by applicable law or agreed to in writing, software\n// distributed under the License is distributed on an \"AS IS\" BASIS,\n// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\n// See the License for the specific language governing permissions and\n// limitations under the License.\n\n// +build ignore\n\npackage main\n\nvar Time float\nvar Cursor vec2\nvar Image texture2d\n\nfunc Vertex(position vec2, texCoord vec2, color vec4) (vec4, vec2) {\n\treturn mat4(\n\t\t2/viewportSize().x, 0, 0, 0,\n\t\t0, 2/viewportSize().y, 0, 0,\n\t\t0, 0, 1, 0,\n\t\t-1, -1, 0, 1,\n\t) * vec4(position, 0, 1), texCoord\n}\n\nfunc Fragment(position vec4, texCoord vec2) vec4 {\n\t// TODO: Instead of using texture2D directly, define and use special functions for Ebiten images.\n\treturn texture2D(Image, texCoord)\n}\n")
diff --git a/examples/shader/main.go b/examples/shader/main.go
index c28b7ab9f..8f3a7cf1b 100644
--- a/examples/shader/main.go
+++ b/examples/shader/main.go
@@ -125,16 +125,14 @@ func (g *Game) Draw(screen *ebiten.Image) {
 	cx, cy := ebiten.CursorPosition()
 
 	op := &ebiten.DrawTrianglesWithShaderOptions{}
-	switch g.idx {
-	case 0:
-		op.Uniforms = []interface{}{
-			float32(g.time) / 60,                // Time
-			[]float32{float32(cx), float32(cy)}, // Cursor
-		}
-	default:
-		op.Uniforms = []interface{}{
+	op.Uniforms = []interface{}{
+		float32(g.time) / 60,                // Time
+		[]float32{float32(cx), float32(cy)}, // Cursor
+	}
+	if g.idx != 0 {
+		op.Uniforms = append(op.Uniforms,
 			gophersImage, // Image
-		}
+		)
 	}
 	screen.DrawTrianglesWithShader(vs, is, s, op)