Remove third_party/golang.org/x/mobile as it is no longer used with Go 1.5.

third_party/go/src/golang.org/x/mobile/sprite/glsprite/glsprite.go

-// Copyright 2014 The Go 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 glsprite implements a sprite Engine using OpenGL ES 2.
-//
-// Each sprite.Texture is loaded as a GL texture object and drawn
-// to the screen via an affine transform done in a simple shader.
-package glsprite // import "golang.org/x/mobile/sprite/glsprite"
-
-import (
-        "image"
-        "image/draw"
-
-        "golang.org/x/mobile/f32"
-        "golang.org/x/mobile/geom"
-        "golang.org/x/mobile/gl/glutil"
-        "golang.org/x/mobile/sprite"
-        "golang.org/x/mobile/sprite/clock"
-)
-
-type node struct {
-        // TODO: move this into package sprite as Node.EngineFields.RelTransform??
-        relTransform f32.Affine
-}
-
-type texture struct {
-        glImage *glutil.Image
-        b       image.Rectangle
-}
-
-func (t *texture) Bounds() (w, h int) { return t.b.Dx(), t.b.Dy() }
-
-func (t *texture) Download(r image.Rectangle, dst draw.Image) {
-        panic("TODO")
-}
-
-func (t *texture) Upload(r image.Rectangle, src image.Image) {
-        draw.Draw(t.glImage.RGBA, r, src, src.Bounds().Min, draw.Src)
-        t.glImage.Upload()
-}
-
-func (t *texture) Unload() {
-        panic("TODO")
-}
-
-func Engine() sprite.Engine {
-        return &engine{
-                nodes: []*node{nil},
-        }
-}
-
-type engine struct {
-        glImages map[sprite.Texture]*glutil.Image
-        nodes    []*node
-
-        absTransforms []f32.Affine
-}
-
-func (e *engine) Register(n *sprite.Node) {
-        if n.EngineFields.Index != 0 {
-                panic("glsprite: sprite.Node already registered")
-        }
-        o := &node{}
-        o.relTransform.Identity()
-
-        e.nodes = append(e.nodes, o)
-        n.EngineFields.Index = int32(len(e.nodes) - 1)
-}
-
-func (e *engine) Unregister(n *sprite.Node) {
-        panic("todo")
-}
-
-func (e *engine) LoadTexture(src image.Image) (sprite.Texture, error) {
-        b := src.Bounds()
-        t := &texture{glutil.NewImage(b.Dx(), b.Dy()), b}
-        t.Upload(b, src)
-        // TODO: set "glImage.Pix = nil"?? We don't need the CPU-side image any more.
-        return t, nil
-}
-
-func (e *engine) SetSubTex(n *sprite.Node, x sprite.SubTex) {
-        n.EngineFields.Dirty = true // TODO: do we need to propagate dirtiness up/down the tree?
-        n.EngineFields.SubTex = x
-}
-
-func (e *engine) SetTransform(n *sprite.Node, m f32.Affine) {
-        n.EngineFields.Dirty = true // TODO: do we need to propagate dirtiness up/down the tree?
-        e.nodes[n.EngineFields.Index].relTransform = m
-}
-
-func (e *engine) Render(scene *sprite.Node, t clock.Time) {
-        e.absTransforms = append(e.absTransforms[:0], f32.Affine{
-                {1, 0, 0},
-                {0, 1, 0},
-        })
-        e.render(scene, t)
-}
-
-func (e *engine) render(n *sprite.Node, t clock.Time) {
-        if n.EngineFields.Index == 0 {
-                panic("glsprite: sprite.Node not registered")
-        }
-        if n.Arranger != nil {
-                n.Arranger.Arrange(e, n, t)
-        }
-
-        // Push absTransforms.
-        // TODO: cache absolute transforms and use EngineFields.Dirty?
-        rel := &e.nodes[n.EngineFields.Index].relTransform
-        m := f32.Affine{}
-        m.Mul(&e.absTransforms[len(e.absTransforms)-1], rel)
-        e.absTransforms = append(e.absTransforms, m)
-
-        if x := n.EngineFields.SubTex; x.T != nil {
-                x.T.(*texture).glImage.Draw(
-                        geom.Point{
-                                geom.Pt(m[0][2]),
-                                geom.Pt(m[1][2]),
-                        },
-                        geom.Point{
-                                geom.Pt(m[0][2] + m[0][0]),
-                                geom.Pt(m[1][2] + m[1][0]),
-                        },
-                        geom.Point{
-                                geom.Pt(m[0][2] + m[0][1]),
-                                geom.Pt(m[1][2] + m[1][1]),
-                        },
-                        x.R,
-                )
-        }
-
-        for c := n.FirstChild; c != nil; c = c.NextSibling {
-                e.render(c, t)
-        }
-
-        // Pop absTransforms.
-        e.absTransforms = e.absTransforms[:len(e.absTransforms)-1]
-}