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我已将Draw Text in OpenGL ES Android中的代码调整为我的应用程序，但文本并未真正显示出来。Android OpenGL ES 2.0：文本没有显示
下面是它目前的样子：
绿色矩形框实际上是一个可绘制位图。
我期待某种文字，白色或黑色的背景之上，但没有什么是以往任何时候都显示出来。
下面是文本类的代码。
package gl.es;
import java.nio.*;
import android.content.Context;
import android.graphics.*;
import android.graphics.drawable.Drawable;
import android.opengl.*;
import android.opengl.Matrix;
public class Text {
public int textTexture;
public FloatBuffer textFloatBuffer;
public FloatBuffer textureFloatBuffer;
public int bufferSize;
public int program;
private final int textWidth = 112;
private final int textHeight = 16;
//private float posX;
private int aTextPositionLocation;
private int aTexturePositionLocation;
private int uMatrixLocation;
private int uTextureUnitLocation;
public Text(Context context) {
program = Shader.buildProgram(context, R.raw.text_vert, R.raw.text_frag);
aTextPositionLocation = GLES20.glGetAttribLocation(program, "a_textPosition");
aTexturePositionLocation = GLES20.glGetAttribLocation(program, "a_texturePosition");
uMatrixLocation = GLES20.glGetUniformLocation(program, "u_matrix");
uTextureUnitLocation = GLES20.glGetUniformLocation(program, "u_textureUnit");
textTexture = createTexture(context);
setBuffer();
//posX = 0f;
}
public int createTexture(Context context) {
//Create empty mutable bitmap.
Bitmap bitmap = Bitmap.createBitmap(textWidth, textHeight, Bitmap.Config.ARGB_8888);
//Use Canvas to paint over it.
Canvas canvas = new Canvas(bitmap);
bitmap.eraseColor(0);
//Draw background
Drawable background = context.getResources().getDrawable(R.drawable.text_bg);
background.setBounds(0, 0, 112, 16);
background.draw(canvas);
//Draw text
Paint textPaint = new Paint();
textPaint.setTextSize(6f);
textPaint.setAntiAlias(false);
textPaint.setARGB(0xff, 0, 0, 0);
//Draw text centered.
canvas.drawText("Text.", 0, 0, textPaint);
int[] texture = new int[1];
GLES20.glGenTextures(1, texture, 0);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, texture[0]);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_LINEAR);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_LINEAR);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_S, GLES20.GL_REPEAT);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_T, GLES20.GL_REPEAT);
GLUtils.texImage2D(GLES20.GL_TEXTURE_2D, 0, bitmap, 0);
//Recycle.
bitmap.recycle();
return texture[0];
}
public void setBuffer() {
final float[] vertexData = {
0f, 0f,
textWidth, 0f,
0f, textHeight,
0f, textHeight,
textWidth, 0f,
textWidth, textHeight
};
final float[] texData = {
0f, 1f,
1f, 1f,
0f, 0f,
0f, 0f,
1f, 1f,
1f, 0f
};
textFloatBuffer = ByteBuffer.allocateDirect(vertexData.length * 4).order(ByteOrder.nativeOrder()).asFloatBuffer();
textFloatBuffer.put(vertexData);
textureFloatBuffer = ByteBuffer.allocateDirect(texData.length * 4).order(ByteOrder.nativeOrder()).asFloatBuffer();
textureFloatBuffer.put(texData);
bufferSize = vertexData.length/2;
}
public void transform(float[] model, float[] projection, float[] mvp) {
Matrix.setIdentityM(model, 0);
Matrix.translateM(model, 0, 0f, 0f, -60f);
Matrix.translateM(model, 0, -60f, 0f, 0f);
Matrix.multiplyMM(mvp, 0, projection, 0, model, 0);
//posX = (posX - 0.3f) % 112f;
}
public void setVertexPointers() {
textFloatBuffer.position(0);
GLES20.glVertexAttribPointer(aTextPositionLocation, 2, GLES20.GL_FLOAT, false, 2 * 4, textFloatBuffer);
GLES20.glEnableVertexAttribArray(aTextPositionLocation);
textFloatBuffer.position(0);
textureFloatBuffer.position(0);
GLES20.glVertexAttribPointer(aTexturePositionLocation, 2, GLES20.GL_FLOAT, false, 2 * 4, textureFloatBuffer);
GLES20.glEnableVertexAttribArray(aTexturePositionLocation);
textureFloatBuffer.position(0);
}
public void draw() {
GLES20.glDrawArrays(GLES20.GL_TRIANGLES, 0, bufferSize);
}
public void useProgram() {
GLES20.glUseProgram(program);
}
public void setUniforms(float[] matrix) {
GLES20.glUniformMatrix4fv(uMatrixLocation, 1, false, matrix, 0);
GLES20.glActiveTexture(GLES20.GL_TEXTURE1);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, textTexture);
GLES20.glUniform1i(uTextureUnitLocation, 1);
}
}
有人能告诉我我在哪里做错了吗？我应该怎么做才能解决这个问题？提前致谢。
更新1： 要回答deathember：
这是当我改变了Matrix.transformM()给你建议了什么会发生什么：
而这里的代码，显示了我将视图矩阵放在哪里：
package gl.es;
import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;
import android.content.Context;
import android.opengl.*;
public class MyRenderer implements GLSurfaceView.Renderer
{
Context context;
Text text;
float eyeX;
float eyeY;
float eyeZ;
private float[] modelMatrix;
private float[] viewMatrix;
private float[] projectionMatrix;
private float[] modelViewProjectionMatrix;
public MyRenderer(Context context) {
this.context = context;
modelMatrix = new float[16];
projectionMatrix = new float[16];
viewMatrix = new float[16];
modelViewProjectionMatrix = new float[16];
}
@Override
public void onSurfaceCreated(GL10 p1, EGLConfig config)
{
// TODO: Implement this method
GLES20.glClearColor(0.4f, 0.8f, 1.0f, 1.0f);
this.text = new Text(this.context);
}
@Override
public void onSurfaceChanged(GL10 p1, int width, int height)
{
// TODO: Implement this method
GLES20.glViewport(0, 0, width, height);
this.setPerspectiveM(45f, (float) (width)/(float) (height), 1f, 200f);
// Did not use view matrix at all for transformations of Text textures.
Matrix.setLookAtM(viewMatrix, 0, 0, 0, 0, 0, 0, 0, 0, 1f, 0); //Unused.
Matrix.setIdentityM(modelMatrix, 0);
projectionMatrix, 0, modelMatrix, 0);
}
@Override
public void onDrawFrame(GL10 p1)
{
// TODO: Implement this method
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
text.transform(modelMatrix, projectionMatrix, modelViewProjectionMatrix);
text.useProgram();
text.setUniforms(modelViewProjectionMatrix);
text.setVertexPointers();
text.draw();
}
private void setPerspectiveM(float fov, float aspectRatio, float near, float far) {
final float anglesInRadians = (float) (fov * Math.PI/180f);
final float angle = (float) (1f/Math.atan(anglesInRadians)/2f);
projectionMatrix[0] = angle/aspectRatio;
projectionMatrix[1] = 0f;
projectionMatrix[2] = 0f;
projectionMatrix[3] = 0f;
projectionMatrix[4] = 0f;
projectionMatrix[5] = angle;
projectionMatrix[6] = 0f;
projectionMatrix[7] = 0f;
projectionMatrix[8] = 0f;
projectionMatrix[9] = 0f;
projectionMatrix[10] = -((far + near)/(far - near));
projectionMatrix[11] = -1f;
projectionMatrix[12] = 0f;
projectionMatrix[13] = 0f;
projectionMatrix[14] = -((2f * far * near)/(far - near));
projectionMatrix[15] = 0f;
}
}
希望有帮助。
你好，这是一个星期。请回来看看。谢谢。 –