diff --git a/internal/graphicscommand/command.go b/internal/graphicscommand/command.go
index 8f8decf30..b1a6161b9 100644
--- a/internal/graphicscommand/command.go
+++ b/internal/graphicscommand/command.go
@@ -126,7 +126,7 @@ func (q *commandQueue) EnqueueDrawImageCommand(dst, src *Image, vertices []float
 
 	q.appendVertices(vertices)
 	q.appendIndices(indices, uint16(q.nextIndex))
-	q.nextIndex += len(vertices) * opengl.Float.SizeInBytes() / opengl.ArrayBufferLayoutTotalBytes()
+	q.nextIndex += len(vertices) / opengl.ArrayBufferLayoutFloatNum()
 	q.tmpNumIndices += len(indices)
 
 	q.doEnqueueDrawImageCommand(dst, src, len(vertices), len(indices), color, mode, filter, split)
diff --git a/internal/opengl/context.go b/internal/opengl/context.go
index e846225bd..e335f9e6f 100644
--- a/internal/opengl/context.go
+++ b/internal/opengl/context.go
@@ -25,8 +25,8 @@ var (
 	elementArrayBuffer bufferType
 	dynamicDraw        bufferUsage
 	staticDraw         bufferUsage
-	Short              DataType
-	Float              DataType
+	short              dataType
+	float              dataType
 
 	zero             operation
 	one              operation
diff --git a/internal/opengl/context_desktop.go b/internal/opengl/context_desktop.go
index e36a6fbdc..9199e4f2c 100644
--- a/internal/opengl/context_desktop.go
+++ b/internal/opengl/context_desktop.go
@@ -61,8 +61,8 @@ func init() {
 	arrayBuffer = gl.ARRAY_BUFFER
 	elementArrayBuffer = gl.ELEMENT_ARRAY_BUFFER
 	dynamicDraw = gl.DYNAMIC_DRAW
-	Short = gl.SHORT
-	Float = gl.FLOAT
+	short = gl.SHORT
+	float = gl.FLOAT
 
 	zero = gl.ZERO
 	one = gl.ONE
@@ -408,7 +408,7 @@ func (c *Context) getAttribLocationImpl(p program, location string) attribLocati
 	return attrib
 }
 
-func (c *Context) vertexAttribPointer(p program, location string, size int, dataType DataType, stride int, offset int) {
+func (c *Context) vertexAttribPointer(p program, location string, size int, dataType dataType, stride int, offset int) {
 	_ = mainthread.Run(func() error {
 		l := c.locationCache.GetAttribLocation(c, p, location)
 		gl.VertexAttribPointer(uint32(l), int32(size), uint32(dataType), false, int32(stride), gl.PtrOffset(offset))
diff --git a/internal/opengl/context_js.go b/internal/opengl/context_js.go
index 6794ddfb8..a891b1f6f 100644
--- a/internal/opengl/context_js.go
+++ b/internal/opengl/context_js.go
@@ -78,8 +78,8 @@ func init() {
 	arrayBuffer = bufferType(c.Get("ARRAY_BUFFER").Int())
 	elementArrayBuffer = bufferType(c.Get("ELEMENT_ARRAY_BUFFER").Int())
 	dynamicDraw = bufferUsage(c.Get("DYNAMIC_DRAW").Int())
-	Short = DataType(c.Get("SHORT").Int())
-	Float = DataType(c.Get("FLOAT").Int())
+	short = dataType(c.Get("SHORT").Int())
+	float = dataType(c.Get("FLOAT").Int())
 
 	zero = operation(c.Get("ZERO").Int())
 	one = operation(c.Get("ONE").Int())
@@ -410,7 +410,7 @@ func (c *Context) getAttribLocationImpl(p program, location string) attribLocati
 	return attribLocation(gl.Call("getAttribLocation", p.value, location).Int())
 }
 
-func (c *Context) vertexAttribPointer(p program, location string, size int, dataType DataType, stride int, offset int) {
+func (c *Context) vertexAttribPointer(p program, location string, size int, dataType dataType, stride int, offset int) {
 	c.ensureGL()
 	gl := c.gl
 	l := c.locationCache.GetAttribLocation(c, p, location)
diff --git a/internal/opengl/context_mobile.go b/internal/opengl/context_mobile.go
index 88d1a0c9d..b49246f4d 100644
--- a/internal/opengl/context_mobile.go
+++ b/internal/opengl/context_mobile.go
@@ -57,8 +57,8 @@ func init() {
 	arrayBuffer = mgl.ARRAY_BUFFER
 	elementArrayBuffer = mgl.ELEMENT_ARRAY_BUFFER
 	dynamicDraw = mgl.DYNAMIC_DRAW
-	Short = mgl.SHORT
-	Float = mgl.FLOAT
+	short = mgl.SHORT
+	float = mgl.FLOAT
 
 	zero = mgl.ZERO
 	one = mgl.ONE
@@ -332,7 +332,7 @@ func (c *Context) getAttribLocationImpl(p program, location string) attribLocati
 	return a
 }
 
-func (c *Context) vertexAttribPointer(p program, location string, size int, dataType DataType, stride int, offset int) {
+func (c *Context) vertexAttribPointer(p program, location string, size int, dataType dataType, stride int, offset int) {
 	gl := c.gl
 	l := c.locationCache.GetAttribLocation(c, p, location)
 	gl.VertexAttribPointer(mgl.Attrib(l), size, mgl.Enum(dataType), false, stride, offset)
diff --git a/internal/opengl/program.go b/internal/opengl/program.go
index e813010b0..3adabb121 100644
--- a/internal/opengl/program.go
+++ b/internal/opengl/program.go
@@ -46,7 +46,7 @@ func (a *arrayBufferLayout) totalBytes() int {
 	}
 	t := 0
 	for _, p := range a.parts {
-		t += Float.SizeInBytes() * p.num
+		t += float.SizeInBytes() * p.num
 	}
 	a.total = t
 	return a.total
@@ -65,8 +65,8 @@ func (a *arrayBufferLayout) enable(program program) {
 	total := a.totalBytes()
 	offset := 0
 	for _, p := range a.parts {
-		GetContext().vertexAttribPointer(program, p.name, p.num, Float, total, offset)
-		offset += Float.SizeInBytes() * p.num
+		GetContext().vertexAttribPointer(program, p.name, p.num, float, total, offset)
+		offset += float.SizeInBytes() * p.num
 	}
 }
 
@@ -101,8 +101,8 @@ func initializeArrayBuferLayout() {
 	}
 }
 
-func ArrayBufferLayoutTotalBytes() int {
-	return theArrayBufferLayout.totalBytes()
+func ArrayBufferLayoutFloatNum() int {
+	return theArrayBufferLayout.totalBytes() / float.SizeInBytes()
 }
 
 // openGLState is a state for
diff --git a/internal/opengl/types.go b/internal/opengl/types.go
index 0453a1c8c..8ca2d01f5 100644
--- a/internal/opengl/types.go
+++ b/internal/opengl/types.go
@@ -21,13 +21,13 @@ type (
 	operation   int
 )
 
-type DataType int
+type dataType int
 
-func (d DataType) SizeInBytes() int {
+func (d dataType) SizeInBytes() int {
 	switch d {
-	case Short:
+	case short:
 		return 2
-	case Float:
+	case float:
 		return 4
 	default:
 		panic("not reached")