我需要一点帮助来实现OpenGL ES 1.1
我有一个带纹理的简单方形多边形（来自nehe教程）。
多边形有一个位图，当创建多边形时，方法loadGLTexture（GL10 gl，Context context）被调用一次，以加载纹理。
我需要在我的应用中添加功能以更改方块的纹理。
哪种更改多边形纹理的最佳方法？在谷歌找不到合适的方式...
感谢所有
编辑：
public class Square {
//Buffer de vertices
public FloatBuffer vertexBuffer;
//Buffer de coordenadas de texturas
private FloatBuffer textureBuffer;
//Puntero de texturas
private int[] textures = new int[3];
//El item a representar
private Bitmap bitmap; //image with POT dimensions
//size of the polygon:
public float w;
public float h;
//size of the texture
private float textureX;
private float textureY;
//Definición de vertices
public float vertices[] = new float[12];
private float vertices_transformed[] = new float[12];
//Coordenadas (u, v) de las texturas
private float texture[];
// Image ratio
float ratio;
public int id;
Context context;
//Inicializamos los buffers
public Square(Bitmap image, Context context) {
int bitmapW=image.getWidth();
int bitmapH=image.getHeight();
w=1.00f;
h=(float)bitmapH/bitmapW;
float vertices2[] = {
-w, -h, 0.0f, //Bottom Left
w, -h, 0.0f, //Bottom Right
-w, h, 0.0f, //Top Left
w, h, 0.0f //Top Right
};
vertices=vertices2;
//calculamos la siguiente potencia de 2 del lado mas largo del bitmap, alto o ancho.
int nextPOT;
if (bitmapW>bitmapH)
nextPOT=getNextPOT(bitmapW);
else
nextPOT=getNextPOT(bitmapH);
//creamos un nuevo bitmap cuadrado con dimensiones potencia de 2, y dentro de el metemos la imagen
bitmap = Bitmap.createBitmap(nextPOT, nextPOT, Bitmap.Config.ARGB_8888); //crea un bitmap transparente gracias al ARGB_8888
Canvas comboImage = new Canvas(bitmap);
comboImage.drawBitmap(image, 0, 0, null);
comboImage.save();
//calculamos las coordenadas de la textura dentro del bitmap que es potencia de 2
textureX = (float)bitmapW / nextPOT;
textureY = (float)bitmapH / nextPOT;
//creamos el array de la textura, pasándole las coordenadas ya obtenidos
float texture2[] ={
0.0f,textureY,
textureX, textureY,
0.0f, 0.0f,
textureX,0.0f
};
System.out.println("bw:"+bitmapW+" nextPOT:"+nextPOT+" texX:"+textureX);
texture=texture2;
ByteBuffer byteBuf = ByteBuffer.allocateDirect(vertices.length * 4);
byteBuf.order(ByteOrder.nativeOrder());
vertexBuffer = byteBuf.asFloatBuffer();
vertexBuffer.put(vertices);
vertexBuffer.position(0);
byteBuf = ByteBuffer.allocateDirect(texture.length * 4);
byteBuf.order(ByteOrder.nativeOrder());
textureBuffer = byteBuf.asFloatBuffer();
textureBuffer.put(texture);
textureBuffer.position(0);
//setPosition(0,0);
ratio = (float)image.getWidth() / image.getHeight();
image.recycle();
}
//Funcion de dibujado
public void draw(GL10 gl) {
gl.glFrontFace(GL10.GL_CCW);
//gl.glEnable(GL10.GL_BLEND);
//Bind our only previously generated texture in this case
gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[0]);
//Point to our vertex buffer
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, textureBuffer);
//Enable vertex buffer
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
//Set The Color To Blue
//gl.glColor4f(0.5f, 0.5f, 1.0f, 1.0f);
//Draw the vertices as triangle strip
gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, 0, vertices.length / 3);
//Disable the client state before leaving
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
//gl.glDisable(GL10.GL_BLEND);
}
//Carga de texturas
public void loadGLTexture(GL10 gl, Context context) {
//Generamos un puntero de texturas
gl.glGenTextures(1, textures, 0);
//y se lo asignamos a nuestro array
gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[0]);
//Creamos filtros de texturas
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_NEAREST);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MAG_FILTER, GL10.GL_LINEAR);
//Diferentes parametros de textura posibles GL10.GL_CLAMP_TO_EDGE
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_S, GL10.GL_REPEAT);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_T, GL10.GL_REPEAT);
//Usamos Android GLUtils para espcificar una textura de 2 dimensiones para nuestro bitmap
GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmap, 0);
//Checkeamos si el GL context es versión 1.1 y generamos los Mipmaps por Flag. Si no, llamamos a nuestra propia implementación
if(gl instanceof GL11) {
gl.glTexParameterf(GL11.GL_TEXTURE_2D, GL11.GL_GENERATE_MIPMAP, GL11.GL_TRUE);
GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmap, 0);
} else {
buildMipmap(gl, bitmap);
}
//Limpiamos los bitmaps
bitmap.recycle();
}
//Nuestra implementación de MipMap. Escalamos el bitmap original hacia abajo por factor de 2 y lo asignamos como nuevo nivel de mipmap
private void buildMipmap(GL10 gl, Bitmap bitmap) {
int level = 0;
int height = bitmap.getHeight();
int width = bitmap.getWidth();
while(height >= 1 || width >= 1) {
GLUtils.texImage2D(GL10.GL_TEXTURE_2D, level, bitmap, 0);
if(height == 1 || width == 1) {
break;
}
level++;
height /= 2;
width /= 2;
Bitmap bitmap2 = Bitmap.createScaledBitmap(bitmap, width, height, true);
bitmap.recycle();
bitmap = bitmap2;
}
}
//returns the next POT
public static int getNextPOT(int n){
int i = 1;
while(i < n)
i *= 2;
return i;
}
public void setPosition( float x , float y ){
vertexBuffer.put( 0 , vertices[0]+x );
vertexBuffer.put( 3 , vertices[3]+x );
vertexBuffer.put( 6 , vertices[6]+x );
vertexBuffer.put( 9 , vertices[9]+x );
vertexBuffer.put( 1 , vertices[1]+y );
vertexBuffer.put( 4 , vertices[4]+y );
vertexBuffer.put( 7 , vertices[7]+y );
vertexBuffer.put( 10 , vertices[10]+y );
}
public void move( float dx , float dy ){
vertexBuffer.put( 0 , vertexBuffer.get(0)+dx );
vertexBuffer.put( 3 , vertexBuffer.get(3)+dx );
vertexBuffer.put( 6 , vertexBuffer.get(6)+dx );
vertexBuffer.put( 9 , vertexBuffer.get(9)+dx );
vertexBuffer.put( 1 , vertexBuffer.get(1)+dy );
vertexBuffer.put( 4 , vertexBuffer.get(4)+dy );
vertexBuffer.put( 7 , vertexBuffer.get(7)+dy );
vertexBuffer.put( 10 , vertexBuffer.get(10)+dy );
}
//CARGA DE TEXTURAS DIFERENTES PARA EL POLÍGONO
static int[] mTextureNameWorkspace= new int[1];
static int[] mCropWorkspace=new int[4];
public int loadBitmap(Context context, GL10 gl, String imageName) {
BitmapFactory.Options sBitmapOptions = new BitmapFactory.Options();
sBitmapOptions.inPreferredConfig = Bitmap.Config.RGB_565;
sBitmapOptions.inScaled=false;
int textureName = -1;
if (context != null && gl != null) {
gl.glGenTextures(1, mTextureNameWorkspace, 0);
textureName = mTextureNameWorkspace[0];
gl.glBindTexture(GL10.GL_TEXTURE_2D, textureName);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_NEAREST);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MAG_FILTER, GL10.GL_LINEAR);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_S, GL10.GL_CLAMP_TO_EDGE);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_T, GL10.GL_CLAMP_TO_EDGE);
//gl.glTexEnvf(GL10.GL_TEXTURE_ENV, GL10.GL_TEXTURE_ENV_MODE, GL10.GL_REPLACE);
gl.glTexEnvf(GL10.GL_TEXTURE_ENV, GL10.GL_TEXTURE_ENV_MODE, GL10.GL_MODULATE);
Bitmap bitmap = loadImage(imageName, context);
GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmap, 0);
mCropWorkspace[0] = 0;
mCropWorkspace[1] = bitmap.getHeight();
mCropWorkspace[2] = bitmap.getWidth();
mCropWorkspace[3] = -bitmap.getHeight();
bitmap.recycle();
((GL11) gl).glTexParameteriv(GL10.GL_TEXTURE_2D, GL11Ext.GL_TEXTURE_CROP_RECT_OES, mCropWorkspace, 0);
textures[0]=textureName;
}
return textureName;
}
public static Bitmap loadImage( String imageName, Context context){
if( imageName.charAt(0) == '/' ) {
imageName = imageName.substring(1);
}
imageName = imageName + ".png";
Bitmap image = BitmapFactory.decodeStream(getResourceAsStream(imageName, context));
return image;
}
public static InputStream getResourceAsStream( String resourceName, Context context) {
if( resourceName.charAt(0) == '/' ) {
resourceName = resourceName.substring(1);
}
InputStream is = null;
try {
is = context.getAssets().open( resourceName );
} catch (IOException e) {e.printStackTrace();}
return is;
}
}
答案 0 :(得分：0)
答案 1 :(得分：0)
事情比你想象的更复杂。 当你使用loadGLTexture（GL10 gl，Context context）时，opengl会加载你的纹理并将其id保存到int然后在render（多边形）函数中你使用这个id来指定这是你想要绘制的纹理。 您需要先加载纹理，将id保存在diferents int's上，然后使用您想要的纹理ID渲染多边形;
首先加载纹理：
int txDog=loadBitmap(context,gl,R.drawable.dog);//This generetes an opengl texture id with the given image
int txCat=loadBitmap(context,gl,R.drawable.cat);
接下来在多边形的渲染函数中添加一个名为texid的附加参数
public void Render(GL10 gl,int texid);
然后在渲染函数中搜索如下行：
gl.glBindTexture(GL10.GL_TEXTURE_2D, thetexturenameid);
用texid
替换thetexturenameid（或任何已命名的）结束为此绘制多边形：
public void Render(gl,txDog);//if you want the dog texture
public void Render(gl,txCat);//if you want the cat texture
static int[] mTextureNameWorkspace= new int[1];
static int[] mCropWorkspace=new int[4];
public static int loadBitmap(Context context, GL10 gl, int resourceId) {
BitmapFactory.Options sBitmapOptions = new BitmapFactory.Options();
sBitmapOptions.inPreferredConfig = Bitmap.Config.RGB_565;
sBitmapOptions.inScaled=false;
int textureName = -1;
if (context != null && gl != null) {
gl.glGenTextures(1, mTextureNameWorkspace, 0);
textureName = mTextureNameWorkspace[0];
gl.glBindTexture(GL10.GL_TEXTURE_2D, textureName);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_NEAREST);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MAG_FILTER, GL10.GL_LINEAR);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_S, GL10.GL_CLAMP_TO_EDGE);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_T, GL10.GL_CLAMP_TO_EDGE);
// gl.glTexEnvf(GL10.GL_TEXTURE_ENV, GL10.GL_TEXTURE_ENV_MODE, GL10.GL_REPLACE);
gl.glTexEnvf(GL10.GL_TEXTURE_ENV, GL10.GL_TEXTURE_ENV_MODE,GL10.GL_MODULATE);
InputStream is = context.getResources().openRawResource(resourceId);
Bitmap bitmap;
bitmap = BitmapFactory.decodeStream(is, null, sBitmapOptions);
GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmap, 0);
mCropWorkspace[0] = 0;
mCropWorkspace[1] = bitmap.getHeight();
mCropWorkspace[2] = bitmap.getWidth();
mCropWorkspace[3] = -bitmap.getHeight();
bitmap.recycle();
((GL11) gl).glTexParameteriv(GL10.GL_TEXTURE_2D,
GL11Ext.GL_TEXTURE_CROP_RECT_OES, mCropWorkspace, 0);
}
return textureName;
}
这是我能解释的最简单方法