Add hints to override default GLContextAttributes options

browser.go

@@ -67,7 +67,15 @@ func CreateWindow(_, _ int, title string, monitor *Monitor, share *Window) (*Win
 	// Use glfw hints.
 	attrs := defaultAttributes()
 	attrs.Alpha = (hints[AlphaBits] > 0)
+	if _, ok := hints[Depth]; ok {
+		attrs.Depth = (hints[Depth] > 0)
+	}
+	attrs.Stencil = (hints[Stencil] > 0)
 	attrs.Antialias = (hints[Samples] > 0)
+	attrs.PremultipliedAlpha = (hints[PremultipliedAlpha] > 0)
+	attrs.PreserveDrawingBuffer = (hints[PreserveDrawingBuffer] > 0)
+	attrs.PreferLowPowerToHighPerformance = (hints[PreferLowPowerToHighPerformance] > 0)
+	attrs.FailIfMajorPerformanceCaveat = (hints[FailIfMajorPerformanceCaveat] > 0)
 
 	// Create GL context.
 	context, err := newContext(canvas.Underlying(), attrs)

hint_js.go

@@ -7,8 +7,14 @@ var hints = make(map[Hint]int)
 type Hint int
 
 const (
-	AlphaBits Hint = 0x00021004
-	Samples   Hint = 0x0002100D
+	AlphaBits                       Hint = 0x00021004
+	Samples                         Hint = 0x0002100D
+	Depth                           Hint = 0x00021100 // github.com/goxjs/glfw original hint for JS
+	Stencil                         Hint = 0x00021101 // github.com/goxjs/glfw original hint for JS
+	PremultipliedAlpha              Hint = 0x00021102 // github.com/goxjs/glfw original hint for JS
+	PreserveDrawingBuffer           Hint = 0x00021103 // github.com/goxjs/glfw original hint for JS
+	PreferLowPowerToHighPerformance Hint = 0x00021104 // github.com/goxjs/glfw original hint for JS
+	FailIfMajorPerformanceCaveat    Hint = 0x00021105 // github.com/goxjs/glfw original hint for JS
 )
 
 func WindowHint(target Hint, hint int) {