fix doc

pixelgl/interface.go

@@ -9,7 +9,7 @@ package pixelgl
 // you enter (load, bind) that object's state, then do something with it, and then leave the state. That 'something'
 // in between, let's call it sub (as in subroutine).
 //
-// The recommended way to implement a Doer is to wrap another Doer (vertex array wrap texture and so on), let's call
+// The recommended way to implement a Doer is to wrap another Doer (vertex array wraps texture and so on), let's call
 // it parent. Then the Do method will look like this:
 //
 //   func (o *MyObject) Do(sub func()) {

pixelgl/orphan.go

@@ -2,7 +2,7 @@ package pixelgl
 
 import "github.com/go-gl/gl/v3.3-core/gl"
 
-// This file defines functions that can operate without a parent BeginEnder.
+// This file defines functions that can operate without a parent Doer.
 
 // Clear clears the current context..
 func Clear(r, g, b, a float64) {

pixelgl/vertex.go

@@ -98,7 +98,7 @@ type VertexArray struct {
 	count  int
 }
 
-// NewVertexArray creates a new vertex array and wraps another BeginEnder around it.
+// NewVertexArray creates a new vertex array and wraps another Doer around it.
 func NewVertexArray(parent Doer, format VertexFormat, mode VertexDrawMode, usage VertexUsage, data []float64) (*VertexArray, error) {
 	va := &VertexArray{
 		parent: parent,