我正在使用 OpenGL|ES 2.0 创建一个简单的 2D 正方形。我正在努力让纹理正常工作。请在这方面帮助我。我附上了下面的代码：
GFXUtils：
public class GFXUtils {
public static final String TAG = "GFXUtils";
public static final int COORDS_PER_VERTEX = 3;
public static final int COORDS_PER_TEXTURE = 2;
public static int vertexStride = COORDS_PER_VERTEX * 4; // bytes per vertex
public static int textureStride = COORDS_PER_TEXTURE * 4; // bytes per vertex
public static Context Context = null;
public static SparseIntArray textures = new SparseIntArray();
public static int loadShader(int type, String shaderCode){
// create a vertex shader type (GLES20.GL_VERTEX_SHADER)
// or a fragment shader type (GLES20.GL_FRAGMENT_SHADER)
int shader = GLES20.glCreateShader(type);
// add the source code to the shader and compile it
GLES20.glShaderSource(shader, shaderCode);
GLES20.glCompileShader(shader);
return shader;
}
public static void checkGlError(String glOperation) {
int error;
while ((error = GLES20.glGetError()) != GLES20.GL_NO_ERROR) {
Log.e(TAG, glOperation + ": glError " + error);
throw new RuntimeException(glOperation + ": glError " + error);
}
}
public static void loadTexture(final int resourceId)
{
final int[] textureHandle = new int[1];
GLES20.glGenTextures(1, textureHandle, 0);
if (textureHandle[0] != 0)
{
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inScaled = false; // No pre-scaling
// Read in the resource
final Bitmap bitmap = BitmapFactory.decodeResource(Context.getResources(), resourceId, options);
// Bind to the texture in OpenGL
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, textureHandle[0]);
// Set filtering
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_NEAREST);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_NEAREST);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_S, GLES20.GL_CLAMP_TO_EDGE);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_T, GLES20.GL_CLAMP_TO_EDGE);
// Load the bitmap into the bound texture.
GLUtils.texImage2D(GLES20.GL_TEXTURE_2D, 0, bitmap, 0);
// Recycle the bitmap, since its data has been loaded into OpenGL.
bitmap.recycle();
}
if (textureHandle[0] == 0)
{
throw new RuntimeException("Error loading texture.");
}
textures.append(resourceId, textureHandle[0]);
}
}
顶点：
public class Vertex
{
public FloatBuffer floatBuffer; // buffer holding the vertices
public ShortBuffer indexBuffer;
public int numVertices;
public int numIndeces;
//public float vertex[];
public Vertex (float[] vertex, int coordsPerVertex)
{
//this.vertex = vertex;
this.setVertices(vertex, coordsPerVertex);
}
public Vertex (float[] vertex, short[] indices, int coordsPerVertex)
{
//this.vertex = vertex;
this.setVertices(vertex, coordsPerVertex);
this.setIndices(indices);
}
private void setVertices(float vertex[], int coordsPerVertex)
{
// a float has 4 bytes so we allocate for each coordinate 4 bytes
ByteBuffer factory = ByteBuffer.allocateDirect (vertex.length * 4);
factory.order (ByteOrder.nativeOrder ());
// allocates the memory from the byte buffer
floatBuffer = factory.asFloatBuffer ();
// fill the vertexBuffer with the vertices
floatBuffer.put (vertex);
// set the cursor position to the beginning of the buffer
floatBuffer.position (0);
numVertices = vertex.length / coordsPerVertex;
}
protected void setIndices(short[] indices) {
ByteBuffer ibb = ByteBuffer.allocateDirect(indices.length * 2);
ibb.order(ByteOrder.nativeOrder());
indexBuffer = ibb.asShortBuffer();
indexBuffer.put(indices);
indexBuffer.position(0);
numIndeces = indices.length;
}
}
更新广场：
public class Square{
private static final String TAG = "Square";
public float[] rotation = {0.0f,0.0f,45.0f};
public float[] scale = {100.0f,100f,100f};
public float[] position = {0.0f,0.0f,100f};
public float[] color = { 0.0f, 0.0f, 1.0f, 1.0f };
private int textureRef = -1;
private int mMVPMatrixHandle;
protected int DRAW_MODE = GLES20.GL_TRIANGLES;
protected int mProgram;
protected int mPositionHandle;
protected Vertex vertices;
protected Vertex texture;
private int mColorHandle;
private int vsTextureCoord;
private int fsTexture;
protected float[] result_matrix = new float[16];
private final String vertexShaderCode =
"uniform mat4 uMVPMatrix;" +
"attribute vec4 vPosition;" +
"attribute vec2 TexCoordIn;" +
"varying vec2 TexCoordOut;" +
"void main() {" +
//the matrix must be included as a modifier of gl_Position
" gl_Position = uMVPMatrix * vPosition;" +
" TexCoordOut = TexCoordIn;" +
"}";
private final String fragmentShaderCode =
"precision mediump float;" +
"uniform vec4 vColor;" +
"uniform sampler2D Texture;" +
"varying lowp vec2 TexCoordOut;" +
"void main() {" +
" gl_FragColor = vColor;" +
"}";
//I am fully aware that I am not using the texture by assigning the colour, but until I can actually SEND the texture through, there would be no point.
static float squareCoords[] = { -0.5f, 0.5f, 0.0f, // top left
-0.5f, -0.5f, 0.0f, // bottom left
0.5f, -0.5f, 0.0f, // bottom right
0.5f, 0.5f, 0.0f }; // top right
private short drawOrder[] = { 0, 1, 2, 0, 2, 3 }; // order to draw vertices
public Square(int textureResourceId) {
int vertexShader = GFXUtils.loadShader(GLES20.GL_VERTEX_SHADER, vertexShaderCode);
int fragmentShader = GFXUtils.loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentShaderCode);
mProgram = GLES20.glCreateProgram(); // create empty OpenGL ES Program
GLES20.glAttachShader(mProgram, vertexShader); // add the vertex shader to program
GLES20.glAttachShader(mProgram, fragmentShader); // add the fragment shader to program
GLES20.glLinkProgram(mProgram); // creates OpenGL ES program executables
textureRef = GFXUtils.textures.get(textureResourceId);
// initialize vertex byte buffer for shape coordinates
vertices = new Vertex(squareCoords, drawOrder, GFXUtils.COORDS_PER_VERTEX);
texture = new Vertex (new float[]
{
1.0f, 0.0f,
0.0f, 0.0f,
1.0f, 1.0f,
0.0f, 1.0f,
}, GFXUtils.COORDS_PER_TEXTURE);
DRAW_MODE = GLES20.GL_TRIANGLE_FAN;
}
private void getHandles()
{
//get handle to vertex shader's vPosition member
mPositionHandle = GLES20.glGetAttribLocation(mProgram, "vPosition");
if (mPositionHandle == -1) Log.e(TAG, "vPosition not found");
//get handle to fragment shader's vColor member
mColorHandle = GLES20.glGetUniformLocation(mProgram, "vColor");
if (mColorHandle == -1) Log.e(TAG, "vColor not found");
//get handle to shape's transformation matrix
mMVPMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uMVPMatrix");
if (mMVPMatrixHandle == -1) Log.e(TAG, "uMVPMatrix not found");
//get handle to texture coordinate variable
vsTextureCoord = GLES20.glGetAttribLocation(mProgram, "TexCoordIn");
if (vsTextureCoord == -1) Log.e(TAG, "TexCoordIn not found");
//get handle to shape's texture reference
fsTexture = GLES20.glGetUniformLocation(mProgram, "Texture");
if (fsTexture == -1) Log.e(TAG, "Texture not found");
}
private void translateRotateScale(float[] matrix, float[] perspectiveMatrix)
{
for (int i= 0; i < perspectiveMatrix.length;i++)
matrix[i] = perspectiveMatrix[i];
Matrix.translateM(matrix, 0, position[0], position[1], position[2]);
Matrix.rotateM(matrix, 0, rotation[0], 1.0f, 0.0f, 0.0f);
Matrix.rotateM(matrix, 0, rotation[1], 0.0f, 1.0f, 0.0f);
Matrix.rotateM(matrix, 0, rotation[2], 0.0f, 0.0f, 1.0f);
Matrix.scaleM(matrix, 0, scale[0], scale[1], scale[2]);
}
public void draw(float[] mvpMatrix) {
rotation[2]+=0.5;
// Add program to OpenGL ES environment
GLES20.glUseProgram(mProgram);
GFXUtils.checkGlError("using program");
//Housekeeping
getHandles();
translateRotateScale(result_matrix, mvpMatrix);
//end housekeeping
// Set color for drawing the shape
GLES20.glUniform4fv(mColorHandle, 1, color, 0);
// Apply the projection and view transformation
GLES20.glUniformMatrix4fv(mMVPMatrixHandle, 1, false, result_matrix, 0);
GFXUtils.checkGlError("glUniformMatrix4fv");
// Prepare the shape coordinate data
GLES20.glVertexAttribPointer(mPositionHandle, GFXUtils.COORDS_PER_VERTEX,
GLES20.GL_FLOAT, false,
GFXUtils.vertexStride, vertices.floatBuffer);
GFXUtils.checkGlError("load vertex buffer");
GLES20.glVertexAttribPointer(vsTextureCoord, GFXUtils.COORDS_PER_TEXTURE,
GLES20.GL_FLOAT, false,
GFXUtils.textureStride, texture.floatBuffer);
GFXUtils.checkGlError("load texture buffer - " + vsTextureCoord);
// Enable a handle to the shape vertices
GLES20.glEnableVertexAttribArray(mPositionHandle);
GFXUtils.checkGlError("enable position handle");
GLES20.glEnableVertexAttribArray(vsTextureCoord);
GFXUtils.checkGlError("enable texture handle");
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GFXUtils.checkGlError("activtexture");
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, textureRef);
GFXUtils.checkGlError("bindtexture");
GLES20.glUniform1i(fsTexture, 0);
GFXUtils.checkGlError("uniformi");
//Draw the shape
GLES20.glDrawElements(DRAW_MODE, vertices.numIndeces, GLES20.GL_UNSIGNED_SHORT, vertices.indexBuffer);
GFXUtils.checkGlError("glDrawArrays with " + vertices.numVertices + " vertices");
//Disable vertex array
GLES20.glDisableVertexAttribArray(vsTextureCoord);
GLES20.glDisableVertexAttribArray(mPositionHandle);
GFXUtils.checkGlError("glDisableVertexAttribArray for position");
}
}
更新但它现在找不到 fsTexture 的“纹理”sampler2D 参数。图片在这里：
我看过以下内容：
Android：OpenGL ES 2.0 - 纹理始终为黑色
使用纹理绘制多个对象
Android OpenGLES 2.0 纹理映射不起作用
Android 的 OpenGL ES 2.0 中的纹理
http://www.learnopengles.com/android-lesson-six-an-introduction-to -texture-filtering/
http://www.learnopengles.com/android-lesson-four-introducing-basic-texturing/
http://blog.shayanjaved.com/2011/05/13/android-opengl-es-2 -0-render-to-texture/
http://www.raywenderlich.com/4404/opengl-es-2-0-for-iphone-tutorial-part-2-textures
http://androgeek.info/?p =167