鲲鹏it教育android课件-30.opengl基础应用es简明开发教程

AndroidOpenGLES概apiDemosGraphicsOpenGLESOpenGLES要用来开发3D形应用的。OpenGLES(OpenGLforEmbeddedSystems)OpenGL图形API的子集，针对、PDA和游戏主机等嵌入式设备而设计。下面是百科中对应OpenGLES的简介OpenGLES是从OpenGL裁剪定制而来的，去除了glBegin/glEnd，OpenGLES1.x对固定管线硬件的，OpenGLES2.x对可编程管线硬件。OpenGLES1.0OpenGL1.3基础的，OpenGLES1.1是以OpenGL1.5规范为基础的，它们分别又支持commoncommonliteprofileliteprofilecommonprofileOpenGLES2.0OpenGL2.0范定义的，commonprofile2005-8，引入了对可编程管线的支持。AndroidApiDemosOpenGLESOpenGLES做个简明开发，可以帮助从未接触过3D开发的程序员了解OpenGL的开发的基本概念和方法，很多移动平台都提供了对OpenGLES开发包的支持，AndroidOpenGLES简明开发主要参考JaywayTeamBlog中OpenGLES开发，这是一个写的比较通俗易懂的开发，适合OpenGLES初学者。除了这个OpenGLES简明开发外，以后将专门针对OpenGLES写个由浅入深的开发，尽请关注。OpenGLESAndoridOpenGLViewAndroidOpenGLESAPIjava.nio等几个包中，其中类GLSurfaceView为这些包中的类OpenGLESAndroidViewOpenGLESAndroidActivityFramebuffer提供了方便使用的调试工具来OpenGLES函数调用以帮助检查错误OpenGLESGLSurfaceView开始，设置GLSurfaceViewOpenGLView1publicvoid setRenderer(GLSurfaceView.Rendererrenderer)1//Calledwhenthesurfaceiscreatedorrecreated.2publicvoidonSurfaceCreated(GL10gl,EGLConfigconfig)4//Calledtodrawthecurrentframe.5publicvoidonDrawFrame(GL10gl)67//Calledwhenthesurfacechanged8publicvoidonSurfaceChanged(GL10gl,intwidth,intonSurfaceCreated参数，比如：背景色，是否打开z-buffer onSurfaceChanged:在横向<->纵向互换时。此时可以重新设置绘制的比率。OpenGLESAndroid项目:OpenGLESTutorial,TutorialPartI.javapublicclassTutorialPartIextendsActivity//CalledwhentheactivityisfirstpublicvoidonCreate(BundlesavedInstanceState)this.requestWindowFeature(Window.FEATURE_NO_TITLE);//WindowManager.LayoutParams.FLAG_FULLSCREEN);//(NEW)GLSurfaceViewview=newview.setRenderer(new}publicclassOpenGLRendererimplementsRenderer{publicvoidonSurfaceCreated(GL10gl,EGLConfigconfig)//Setthebackgroundcolortoblack(rgbagl.glClearColor(0.0f,0.0f,0.0f, //OpenGL//EnableSmoothShading,defaultnotreallygl.glShadeModel(GL10.GL_SMOOTH);//OpenGL//Depthbuffergl.glClearDepthf(1.0f);//OpenGL//Enablesdepthgl.glEnable(GL10.GL_DEPTH_TEST);//OpenGL//Thetypeofdepthtestingtogl.glDepthFunc(GL10.GL_LEQUAL);//OpenGL//Reallynicegl.glHint(GL10.GL__CORRECTION_HINT,//OpenGL}publicvoidonDrawFrame(GL10gl)//Clearsthescreenanddepthgl.glClear(GL10.GL_COLOR_BUFFER_BIT|//OpenGL}publicvoidonSurfaceChanged(GL10gl,intwidth,intheight)//Setsthecurrentviewporttothenew

gl.glViewport(0,0,width,height);//OpenGL//Selecttheprojectionmatrixgl.glMatrixMode(GL10.GL_PROJECTION);//OpenGLdocs.//Resettheprojectionmatrixgl.glLoadIdentity();//OpenGLdocs.//CalculatetheaspectratioofthewindowGLU.glu(gl,45.0f,(float)width/(float)height,0.1f,100.0f);//Selectthemodelviewmatrixgl.glMatrixMode(GL10.GL_MODELVIEW);//OpenGLdocs.//Resetthemodelviewmatrixgl.glLoadIdentity();//OpenGLdocs.}AndroidOpenGLES应用的最基本的类和方法，可以看作是OpenGLES的”o,world”应用，后3D框架代码：可以作为你自己的OpenGL3D的初始代码3D绘图基本概AndroidOpenGLES3D3D（顶点，边，面，多边形）构成，每个Vertex（顶点3D3DCamera(Vertex)。AndroidAndroid1privatefloatvertices[]=2- 1.0f,//0,Top3-1.0f,-1.0f,//1,Bottom41.0f,-1.0f,//2,Bottom5 1.0f,//3,Topjava.ioBuffer1//afloatis4bytes,thereforewemultiplythe2//numberifverticeswith4.3ByteBuffervbb=ByteBuffer.allocateDirect(vertices.length*4);5FloatBuffervertexBuffer=vbb.asFloatBuffer();OpenGLES，OpenGLES一个成为”管道Pipeline”的机制，这个管道定义了一些“开关”来控制OpenGLESOpenGLESOpenGLOpenGLVertexbufferBuffer。2gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);//OpenGLdocs.3//Specifiesthelocationanddataformatofanarrayofvertex4//coordinatestousewhenrendering.6Whenyouaredonewiththebufferdon'tforgettodisableit.7//Disabletheverticesbuffer.8gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);//OpenGLdocs.Edge（边3DOpenGLFace(面的变化影响到连接面的所有顶点和边，面多边形。下图黄域代表一个面。定义面的顶点的顺序很重要Polygon（多边形多边形由多个面（三角形）拼接而成，在三上，多边形并一定表示这个PolygonFront)，下图黄域为一个多边形。Androidbuffer1privateshort[]indices={0,1,2,0,2,32Togainsomeperformancewealsoputthisonesinabyte3//shortis2bytes,thereforewemultiplythenumberifvertices5ByteBufferibb=ByteBuffer.allocateDirect(indices.length*7ShortBufferindexBuffer=Render渲染我们已定义好了多边形下面就要了解如和使用OpenGLES的API来绘（渲染）这个多边形了。OpenGLES voidglDrawArrays(intmode,intfirst,int VetexBuffervertexBufferpublicvoidglDrawElements(intmode,intcount,inttype,Bufferindices)indicesBuffer指定。前面我们已定义里顶点数组，因此采用glDrawElements来绘制多边形Square.java1package23import4import5import6import78import910publicclassSquare//Ourprivatefloatvertices[]=- 1.0f, //0,Top-1.0f,-1.0f, //1,Bottom1.0f,-1.0f, //2,Bottom 1.0f, //3,Top//Theorderweliketoconnectprivateshort[]indices={0,1,2,2,3//OurvertexprivateFloatBuffer//OurindexprivateShortBufferpublicSquare()//afloatis4bytes,therefore//multiplythenumber//verticeswith32ByteBuffer33=ByteBuffer.allocateDirect(vertices.length*vertexBuffer=//shortis2bytes,thereforewe//thenumber//verticeswithByteBuffer43=ByteBuffer.allocateDirect(indices.length*indexBuffer=}50*Thisfunctiondrawsoursquareon*@parampublicvoiddraw(GL10gl)//Counter-clockwise//Enableface//Whatfacestoremovewiththeface//Enabledtheverticesbufferfor//andtobeused////Specifiesthelocationanddataformat//anarrayof//coordinatestousewhengl.glVertexPointer(3,GL10.GL_FLOAT,gl.glDrawElements(GL10.GL_TRIANGLES,GL10.GL_UNSIGNED_SHORT,//Disablethevertices//Disableface

}OpenGLRendererSquare1//Initializeoursquare.2Squaresquare=newSquare();publicvoidonDrawFrame(GL10gl)1//Drawour来绘制这个正方形编译运行什么也没显示，这是为什么呢？这是因为OpenGLES从当前位置开始渲染，缺省坐标为(0,0,0)，和Viewport的坐标一样，相当于把画面放在眼前，对应这种情况OpenGL不会渲染离viewPort很近的画面，1//Translates4unitsintothescreen.2gl.glTranslatef(0,0,-4);调用onDrawFrame时，每次都再向后移动4单位，需要加上重置Matrix1//ReplacethecurrentmatrixwiththeidentitymatrixpublicvoidonDrawFrame(GL10gl)//Clearsthescreenanddepthgl.glClear(GL10.GL_COLOR_BUFFER_BITgl.glTranslatef(0,0,-//Drawoursquare.draw(gl);//(NEW9本篇代码3D标变3Dtransformations。CoordinateSystem标系OpenGLTranslate平移变方法public voidglTranslatef(floatx,floaty,floatz)用在上个例子中我们把需要显示的正方形后移了4个单位就是使用的坐标的平移Rotate旋publicvoidglRotatef(floatangle,floatx,floaty,float比如你选择一个首先按下列顺31gl.glRotatef(90f,1.0f,0.0f,0.0f);2gl.glRotatef(90f,0.0f,1.0f,0.0f);3gl.glRotatef(90f,0.0f,0.0f,1gl.glRotatef(90f,-1.0f,0.0f,2gl.glRotatef(90f,0.0f,-1.0f,3gl.glRotatef(90f,0.0f,0.0f,-1gl.glRotatef(90f,0.0f,0.0f,-2gl.glRotatef(90f,0.0f,-1.0f,3gl.glRotatef(90f,-1.0f,0.0f,glRotatef(angle,x,y,z)glRotatef(-angle,x,y,z)是等价的，但选择变换的顺序直接影响最终坐标变换的结果。角度为正时表示逆时Translate&Rotate（平移和旋转组合变换Mesh（网格，构成三维形体的基本单位）标变换的顺序也直接影响最终的结果。MeshScale（缩放方法public voidglScalef(floatx,floaty,floatz)用于缩放gl.glScalef(2f,2f,2f)2.Translate&Scale（平移和缩放组合变换1gl.glTranslatef(2,0,0);2gl.glScalef(0.5f,0.5f,0.5f);1gl.glScalef(0.5f,0.5f,0.5f);2gl.glTranslatef(2,0,0);矩阵操作，单位 voidglLoadIdentity void和 voidglPopMatrix在进行坐标变换的一个好习惯是在变换前使用glPushMatrix保存当前矩阵，完glPopMatrix3A,B,C。进行缩放变换，使的BA50%，CB50%。然后以屏幕中心逆时针旋转A，BA心顺时针旋转，C以BonDrawFramepublicvoidonDrawFrame(GL10gl)//Clearsthescreenanddepth|//Replacethecurrentmatrixwiththeidentity//Translates10unitsintothegl.glTranslatef(0,0,-9//SQUARE//Savethecurrent//RotatesquareAcounter-gl.glRotatef(angle,0,0,//Drawsquare//Restorethelast20//SQUARE21//Savethecurrent//RotatesquareBbeforemoving//makingitrotatearoundgl.glRotatef(-angle,0,0,//Movesquaregl.glTranslatef(2,0,//Scaleitto50%ofsquaregl.glScalef(.5f,.5f,//Drawsquare//SQUARE//Savethecurrent//Maketherotationaroundgl.glRotatef(-angle,0,0,gl.glTranslatef(2,0,//Scaleitto50%ofsquaregl.glScalef(.5f,.5f,//Rotatearoundit'sowngl.glRotatef(angle*10,0,0,//Drawsquare//Restoretothematrixasitwas//Restoretothematrixasitwas//Incresethe}添加颜（网格）添加颜色。OpenGLESRGBA（红，绿，蓝，Hex0xFF00FF或十进制格式(255,0,255)，0…100，1255（0xFF)最简单的上色方法叫做顶点(Vertxtcoloring)，可以使用单色，也可以定义颜色渐变或者使用材质（Brush）。Flatcoloring（单色 voidglColor4f(floatred,floatgreen,floatblue,floatred,green,blue1，代表白色。这也是为什么前面显示的正方形都是1publicvoiddraw(GL10gl)2gl.glColor4f(0.5f,0.5f,1.0f,3OpenGLRenderersquareFlatColoredSquare1privateFlatColoredSquaresquare=newSmoothcoloring（平滑颜色渡当给每个顶点定义一个颜色时，OpenGL1//Thecolorsmappedtothevertices.2float[]colors={30415263Buffer1//floathas4bytes,colors(RGBA)*4bytes2ByteBuffercbb3=ByteBuffer.allocateDirect(colors.length*5colorBuffer=cbb.asFloatBuffer();1publicvoiddraw(GL10gl)2gl.glVertexPointer(3,GL10.GL_FLOAT,0,3//Enablethecolorarraybufferto//usedduring//Pointoutthewherethecolorbuffergl.glColorPointer(4,GL10.GL_FLOAT,0,911//Disablethecolorbuffer.真正的3D图OpenGLES3D（平面上也是有两个Mesh构成的。本篇将介绍使用Mesh构成四面体，椎体等基本空间形Design设OpenGL“CompositePattern”，本篇Mesh,Mesh（三角形网格），其基本定义如下：publicclassMesh//OurvertexprivateFloatBufferverticesBuffer=null;//OurindexprivateShortBufferindicesBuffer=null;//ThenumberofprivateintnumOfIndices=-//Flatprivatefloat[] =newfloat[]{1.0f,1.0f,1.0f,1.0f};//SmoothprivateFloatBuffercolorBuffer=null; //Translate publicfloatx= publicfloaty= publicfloatz=//Rotatepublicfloatrx=floatry=floatrz=voiddraw(GL10gl)//Counter-clockwise//Enableface//Whatfacestoremovewiththeface//Enabledtheverticesbufferforwriting//tobeused////Specifiesthelocationanddata//ofanarrayof//coordinatestousewhengl.glVertexPointer(3,GL10.GL_FLOAT,0,//Setflatgl.glColor4f(rgba[0],rgba[1],rgba[2],//Smoothif(colorBuffer!=null)//Enablethecolorarraybufferto//usedduringgl.glColorPointer(4,GL10.GL_FLOAT,0,}gl.glTranslatef(x,y,gl.glRotatef(rx,1,0,gl.glRotatef(ry,0,1,gl.glRotatef(rz,0,0,//Pointoutthewherethecolorbuffergl.glDrawElements(GL10.GL_TRIANGLES,GL10.GL_UNSIGNED_SHORT,//Disablethevertices//Disableface} protectedvoidsetVertices(float[]vertices)

//afloatis4bytes,//wemultiplythenumber//verticeswith4.ByteBuffervbb=ByteBuffer.allocateDirect(vertices.length*4);verticesBuffer=vbb.asFloatBuffer();}protectedvoidsetIndices(short[]indices)//shortis2bytes,thereforewe//thenumber//verticeswith2.ByteBufferibb=ByteBuffer.allocateDirect(indices.length*2);indicesBuffer=ibb.asShortBuffer();numOfIndices=}protectedvoidsetColor(floatred,floatgreen,floatblue,floatalpha){//Settingtheflatcolor.rgba[0]=red;rgba[1]=green;rgba[2]=blue;rgba[3]=}protectedvoidsetColors(float[]colors)//floathas4bytes.ByteBuffercbb=ByteBuffer.allocateDirect(colors.length*4);colorBuffer=cbb.asFloatBuffer();}setVerticessetIndicessetColor/setColorsx,y,zrx,ry,rz义为沿XZ轴方向长度，高度为YSegments游戏场景中，构造地貌，使的Z0.10.1SegmentsOpenGLSegments//Letyoudecidethesizeoftheplanebutstillonlyonesegment.publicPlane(floatwidth,floatheight)//ForallayourpublicPlane(floatwidth,floatheight,intwidthSegments,int1unit1unit4Segments，使用图形表示如segmentsPlanepublicclassPlaneextendsMeshpublicPlane()this(1,1,1,}5publicPlane(floatwidth,floatheight)this(width,height,1,}9publicPlane(floatwidth,floatheight,intintheightSegments)float[]13=newfloat[(widthSegments+*(heightSegments+1)*short[]16=newshort[(widthSegments+17*(heightSegments+1)*floatxOffset=width/-floatyOffset=height/-floatxWidth=width/floatyHeight=height/intcurrentVertex=intcurrentIndex=shortw=(short)(widthSegments+for(inty=0;y<heightSegments+1;y++)for(intx=0;x<widthSegments+1;x++)vertices[currentVertex]=xOffset+x*vertices[currentVertex+1]=yOffset+y*vertices[currentVertex+2]=currentVertex+=33intn=y*(widthSegments+1)+x;if(y<heightSegments&&x<widthSegments)//Faceindices[currentIndex]=(short)+=++=+//Face+=++=+1+=+1wcurrentIndex+=}}}

}PlaneSegments1publicclassCubeextendsMesh2Cube(floatwidth,floatheight,floatdepth)3/=4/=5/=6floatvertices[]={-width,-height,-depth,//width,-height,-depth,// height,-depth,//- height,-depth,//-width,- depth,//width,- depth,// depth,//- depth,//17shortindices[]={0,4,

}Group可以用来管理多个空间几何形体如果把Mesh比作Android的View,Group可以看作AndroidViewGroupAndroidView的设计也是采用的“CompositeGroupGroup（draw)Group对应的操作（draw)。publicclassGroupextendsMeshprivateVector<Mesh>children=newVector<Mesh>();publicvoiddraw(GL10gl)intsize=for(inti=0;i<size;}11*@param*@param*@seejava.util.Vector#add(int,publicvoidadd(intlocation,Meshobject)children.add(location,}20*@param**@seepublicbooleanadd(Meshobject)return}29**@seepublicvoidclear()}37*@param**@seepublicMeshget(intlocation)return}46*@param**@seepublicMeshremove(intlocation)

return}@param@seepublicbooleanremove(Objectobject){returnchildren.remove(object);}@seepublicintsize(){returnchildren.size();}其它建本例示例代 ，显示结果如下材质渲创建Bitmap对BitmapBitmap文件中或是从网络或是使用代码构造为简单起见本例从资源中：1Bitmapbitmap=要注意的是，有些设备对使用的Bitmap的大小有要求，要求Bitmap的宽度和长创建材质(GeneratingaOpenGL(TextureTextureId。1//Createanintarraywiththenumberoftextureswewant,2//inthiscase1.3int[]textures=new4//lOpenGLtogeneratetextures.5gl.glGenTextures(1,textures,0);texturesTextureID，TextureIdTexture：1//Deleteatexture.2gl.glDeleteTextures(1,textures,0)TextureIdOpenGLTexture：1gl.glBindTexture(GL10.GL_TEXTURE_2D,设置Texture参数TextureTextureTextureOpenGL1//Scaleupifthetextureifsmaller.56//scalelinearlywhenimagesmalledthantextureGL10.GL_LINEARGL10.GL_NEARESTGL10.GL_LINEARUVOpenGLBitmapMesh定义UV坐UVMap指将Bitmap的像素映射到Mesh上的顶点UV坐标定义为左上（0，0），右下角（1，1）（2DTexture)，UVUV（0，1）0，（1，1）21floattextureCoordinates[]={0.0f,21.0f,30.0f,41.0f,0.0f1floattextureCoordinates[]={0.0f,20.5f,30.0f,40.5f,0.0fTexture1floattextureCoordinates[]={0.0f,22.0f,30.0f,42.0f,0.0fUV），OpenGLTextureGL_REPEATTextureGL_CLAMP_TO_EDGE只靠边线绘制一次。BitmapTexture1GLUtils.texImage2D(GL10.GL_TEXTURE_2D,0,bitmap,使用为了能够使用上面定义的Texture，需要创建一Buffer来UV坐标：1FloatBufferbyteBuf=ByteBuffer.allocateDirect(texture.length*4);3textureBuffer=byteBuf.asFloatBuffer();//lingOpenGLtoenable//lOpenGLwhereourtextureisgl.glBindTexture(GL10.GL_TEXTURE_2D,//lOpenGLtoenabletheuseofUV//lingOpenGLwhereourUVcoordinatesgl.glTexCoordPointer(2,GL10.GL_FLOAT,0,910//...heregoestherenderingofthemesh...12//DisabletheuseofUVcoordinates.14//Disabletheuseoftextures.本例代码是在一个平面上（SimplePlane）TextureMeshUV//OurUVtextureprivateFloatBuffermTextureBuffer;4*Setthetexture**@paramprotectedvoidsetTextureCoordinates(float[]textureCoords)//floatis4bytes,thereforewemultiplythenumber//verticeswithByteBufferbyteBuf=textureCoords.length*mTextureBuffer=

BitmapTexture//OurtextureprivateintmTextureId=-3//ThebitmapwewanttoloadasaprivateBitmapmBitmap;7*Setthebitmaptoloadintoa**@param12publicvoidloadBitmap(Bitmapbitmap)

this.mBitmap=bitmap;mShouldLoadTexture=true;*Loadsthe**@param22privatevoidloadGLTexture(GL10gl)//Generateonetextureint[]textures=newgl.glGenTextures(1,textures,mTextureId