OpenGL widget

AUTHORS

@@ -17,6 +17,7 @@ Audrius Karabanovas <[email protected]>
 Benny Siegert <[email protected]>
 Cary Cherng <[email protected]>
 Dmitry Bagdanov <[email protected]>
+Ethan Reesor <[email protected]>
 Ham Yeongtaek <[email protected]>
 Hill <[email protected]>
 iquanxin <[email protected]>

declarative/opengl.go

@@ -0,0 +1,71 @@
+// Copyright 2021 The Walk Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+package declarative
+
+import (
+	"github.com/lxn/walk"
+)
+
+type OpenGL struct {
+	// Window
+
+	Accessibility      Accessibility
+	Background         Brush
+	ContextMenuItems   []MenuItem
+	DoubleBuffering    bool
+	Enabled            Property
+	Font               Font
+	MaxSize            Size
+	MinSize            Size
+	Name               string
+	OnBoundsChanged    walk.EventHandler
+	OnKeyDown          walk.KeyEventHandler
+	OnKeyPress         walk.KeyEventHandler
+	OnKeyUp            walk.KeyEventHandler
+	OnMouseDown        walk.MouseEventHandler
+	OnMouseMove        walk.MouseEventHandler
+	OnMouseUp          walk.MouseEventHandler
+	OnSizeChanged      walk.EventHandler
+	Persistent         bool
+	RightToLeftReading bool
+	ToolTipText        Property
+	Visible            Property
+
+	// Widget
+
+	Alignment          Alignment2D
+	AlwaysConsumeSpace bool
+	Column             int
+	ColumnSpan         int
+	GraphicsEffects    []walk.WidgetGraphicsEffect
+	Row                int
+	RowSpan            int
+	StretchFactor      int
+
+	// OpenGL
+
+	AssignTo    **walk.OpenGL
+	Setup       walk.GLFunc
+	Paint       walk.GLFunc
+	Teardown    walk.GLFunc
+	Style       int
+	PixelFormat []int32 // for wglCreateContextAttribsARB
+	Context     []int32 // for wglCreateContextAttribsARB
+}
+
+func (gl OpenGL) Create(builder *Builder) error {
+	w, err := walk.NewOpenGL(builder.Parent(), uint32(gl.Style), gl.Setup, gl.Paint, gl.Teardown, gl.PixelFormat, gl.Context)
+	if err != nil {
+		return err
+	}
+
+	if gl.AssignTo != nil {
+		*gl.AssignTo = w
+	}
+
+	return builder.InitWidget(gl, w, func() error { return nil })
+}

examples/opengl/triangle/triangle.exe.manifest

@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
+	<assemblyIdentity version="1.0.0.0" processorArchitecture="*" name="SomeFunkyNameHere" type="win32"/>
+	<dependency>
+		<dependentAssembly>
+			<assemblyIdentity type="win32" name="Microsoft.Windows.Common-Controls" version="6.0.0.0" processorArchitecture="*" publicKeyToken="6595b64144ccf1df" language="*"/>
+		</dependentAssembly>
+	</dependency>
+	<application xmlns="urn:schemas-microsoft-com:asm.v3">
+		<windowsSettings>
+			<dpiAwareness xmlns="http://schemas.microsoft.com/SMI/2016/WindowsSettings">PerMonitorV2, PerMonitor</dpiAwareness>
+			<dpiAware xmlns="http://schemas.microsoft.com/SMI/2005/WindowsSettings">True</dpiAware>
+		</windowsSettings>
+	</application>
+</assembly>

examples/opengl/triangle/triangle.go

@@ -0,0 +1,41 @@
+// Copyright 2021 The Walk Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+	"github.com/go-gl/gl/all-core/gl"
+	"github.com/lxn/walk"
+	. "github.com/lxn/walk/declarative"
+)
+
+func main() {
+	MainWindow{
+		Title:   "Walk OpenGL Example",
+		MinSize: Size{320, 240},
+		Layout:  HBox{},
+		Children: []Widget{
+			OpenGL{
+				Setup: func(*walk.OpenGLContext) error {
+					return gl.Init()
+				},
+				Paint: func(glc *walk.OpenGLContext) error {
+					sz := glc.Widget().Size()
+					gl.Viewport(0, 0, int32(sz.Width), int32(sz.Height))
+					gl.Clear(gl.COLOR_BUFFER_BIT)
+					gl.Begin(gl.TRIANGLES)
+					gl.Color3f(1.0, 0.0, 0.0)
+					gl.Vertex2i(0, 1)
+					gl.Color3f(0.0, 1.0, 0.0)
+					gl.Vertex2i(-1, -1)
+					gl.Color3f(0.0, 0.0, 1.0)
+					gl.Vertex2i(1, -1)
+					gl.End()
+					gl.Flush()
+					return nil
+				},
+			},
+		},
+	}.Run()
+}