我已被分配创建此Objective C GPUImage Framework的开源Java端口，以便可以在Android应用程序中使用它。我将尽可能地重新创建它，所有变量名称，函数名称等都是相同的。我正处于开始阶段，我正在尝试移植GPUImageOpenGLESContext.h和GPUImageOpenGLESContext.m（很抱歉，会提供链接，但作为新用户，我无法再添加链接）。
我对这些方法有困难
+ (GLint)maximumTextureSizeForThisDevice;
{
GLint maxTextureSize;
glGetIntegerv(GL_MAX_TEXTURE_SIZE, &maxTextureSize);
return maxTextureSize;
}
+ (GLint)maximumTextureUnitsForThisDevice;
{
GLint maxTextureUnits;
glGetIntegerv(GL_MAX_TEXTURE_IMAGE_UNITS, &maxTextureUnits);
return maxTextureUnits;
}
似乎在Objective C中，你可以简单地调用这些方法，但在Java中你不能。我做了一些搜索，发现大多数人都说使用GLSurfaceView，但这需要一个活动，对吗？我发现这个Get Maximum OpenGL ES 2.0 Texture Size Limit on Android时非常兴奋，但是回复声称代码不起作用。
所以，我的问题是，如何在不是活动的类中获得最小和最大纹理？使用GLSurfaceView？
我也很感激有关如何移植它的任何建议。我从来没有从Objective C移植到Java，所以任何建议都会受到赞赏！
如果它有用，这是我目前的代码：
public class GPUImageOpenGLESContext
{
private static GPUImageOpenGLESContext instance = null;
EGLContext context;
protected GPUImageOpenGLESContext()
{
// This is a protected empty method
// that exists only to prevent
// this singleton object from
// multiple instantiation
return;
}
public enum GPUImageRotationMode {
kGPUImageNoRotation, kGPUImageRotateLeft, kGPUImageRotateRight, kGPUImageFlipVertical,
kGPUImageFlipHorizontal, kGPUImageRotateRightFlipVertical, kGPUImageRotate180
}
public GPUImageRotationMode GPUImageRotationSwapsWidthAndHeight(GPUImageRotationMode rotation)
{
// TODO: Implement GPUImageRotationSwapsWidthAndHeight macro as method
//rotation = ((rotation) == kGPUImageRotateLeft || (rotation) == kGPUImageRotateRight || (rotation) == kGPUImageRotateRightFlipVertical)
return rotation;
}
public static GPUImageOpenGLESContext sharedImageProcessingOpenGLESContext()
{
if (instance == null)
{
instance = new GPUImageOpenGLESContext();
}
return instance;
}
public static void useImageProcessingContext()
{
EGLContext imageProcessingContext = GPUImageOpenGLESContext.sharedImageProcessingOpenGLESContext().context;
if (EGLContext.getEGL() != imageProcessingContext)
{
// In Objective C, this call would be here:
// [EAGLContext setCurrentContext:imageProcessingContext]
// Cannot figure out how to handle this. For now, throws an exception.
throw new RuntimeException("useImageProcessingContext not equal to EGLContext");
}
return;
}
public static int maximumTextureSizeForThisDevice()
{
int[] maxTextureSize = new int[1];
// TODO: See if you can use gl. without an activity
//GL10 gl = new GL10();
//EGL gl = EGLContext.getEGL();
//gl.glGetIntegerv(GL10.GL_MAX_TEXTURE_SIZE, maxTextureSize, 0);
return maxTextureSize[0];
}
public static int maximumTextureUnitsForThisDevice()
{
// TODO: Implement maximumTextureUnitsForThisDevice();
return -1;
}
public static CGSize sizeThatFitsWithinATextureForSize(CGSize inputSize)
{
int maxTextureSize = maximumTextureSizeForThisDevice();
if ((inputSize.width < maxTextureSize) && (inputSize.height < maxTextureSize))
{
return inputSize;
}
CGSize adjustedSize = new CGSize();
if (inputSize.width > inputSize.height)
{
adjustedSize.width = (float)maxTextureSize;
adjustedSize.height = ((float)maxTextureSize / inputSize.width) * inputSize.height;
}
else
{
adjustedSize.height = (float)maxTextureSize;
adjustedSize.width = ((float)maxTextureSize / inputSize.height) * inputSize.width;
}
return adjustedSize;
}
public EGLContext getContext()
{
if (context == null)
{
// TODO: Implement getContext()
}
}
public interface GPUImageInput
{
public void newFrameReadyAtTime(Time frameTime);
public void setInputTextureAtIndex(int newInputTexture, int textureIndex);
public int nextAvailableTextureIndex();
public void setInputSizeAtIndex(CGSize newSize, int textureIndex);
public void setInputRotationAtIndex(GPUImageRotationMode newInputRotation, int textureIndex);
public CGSize maximumOutputSize();
public void endProcessing();
public boolean shouldIgnoreUpdatesToThisTarget();
}
}
答案 0 :(得分：1)
我意识到这是一个旧帖子但你的问题是你没有正确初始化EGLContext。
通常，您希望使用GLSurfaceView或TextureView在View层次结构中实际包含GL内容。 GLSurfaceView将为您处理很多事情，例如正确创建EGLContext和管理渲染线程。 TextureView需要更多的手动工作。
通过上述任何一种方式获得上下文后，您可以使用：
GLES20.glGetIntegerv(GLES20.GL_MAX_TEXTURE_SIZE, size, 0);
假设您已绑定OpenGL ES 2.0 API。首先确保您已正确创建EGLContext并执行EGL和GLES调用，然后您应该能够查询最大纹理大小。
你可以看到Romain Guy关于使用TextureView的帖子，就像你在GLSurfaceView上看到关于管理你自己的EGLContext的细节一样（https://groups.google.com/d/msg/android-developers/U5RXFGpAHPE/IqHeIeGXhr0J）：
GLSurfaceView为您处理GL设置，TextureView不会这样做。 创建EGL时，TextureView可用作本机窗口 表面。这是一个例子（有趣的部分是调用 eglCreateWindowSurface（））：
@Override
public void onSurfaceTextureAvailable(SurfaceTexture surface, int width, int height) {
mRenderThread = new RenderThread(getResources(), surface);
mRenderThread.start();
}
private static class RenderThread extends Thread {
private static final String LOG_TAG = "GLTextureView";
static final int EGL_CONTEXT_CLIENT_VERSION = 0x3098;
static final int EGL_OPENGL_ES2_BIT = 4;
private volatile boolean mFinished;
private final Resources mResources;
private final SurfaceTexture mSurface;
private EGL10 mEgl;
private EGLDisplay mEglDisplay;
private EGLConfig mEglConfig;
private EGLContext mEglContext;
private EGLSurface mEglSurface;
private GL mGL;
RenderThread(Resources resources, SurfaceTexture surface) {
mResources = resources;
mSurface = surface;
}
private static final String sSimpleVS =
"attribute vec4 position;\n" +
"attribute vec2 texCoords;\n" +
"varying vec2 outTexCoords;\n" +
"\nvoid main(void) {\n" +
" outTexCoords = texCoords;\n" +
" gl_Position = position;\n" +
"}\n\n";
private static final String sSimpleFS =
"precision mediump float;\n\n" +
"varying vec2 outTexCoords;\n" +
"uniform sampler2D texture;\n" +
"\nvoid main(void) {\n" +
" gl_FragColor = texture2D(texture, outTexCoords);\n" +
"}\n\n";
private static final int FLOAT_SIZE_BYTES = 4;
private static final int TRIANGLE_VERTICES_DATA_STRIDE_BYTES = 5 * FLOAT_SIZE_BYTES;
private static final int TRIANGLE_VERTICES_DATA_POS_OFFSET = 0;
private static final int TRIANGLE_VERTICES_DATA_UV_OFFSET = 3;
private final float[] mTriangleVerticesData = {
// X, Y, Z, U, V
-1.0f, -1.0f, 0.0f, 0.0f, 0.0f,
1.0f, -1.0f, 0.0f, 1.0f, 0.0f,
-1.0f, 1.0f, 0.0f, 0.0f, 1.0f,
1.0f, 1.0f, 0.0f, 1.0f, 1.0f,
};
@Override
public void run() {
initGL();
FloatBuffer triangleVertices = ByteBuffer.allocateDirect(mTriangleVerticesData.length
* FLOAT_SIZE_BYTES).order(ByteOrder.nativeOrder()).asFloatBuffer();
triangleVertices.put(mTriangleVerticesData).position(0);
int texture = loadTexture(R.drawable.large_photo);
int program = buildProgram(sSimpleVS, sSimpleFS);
int attribPosition = glGetAttribLocation(program, "position");
checkGlError();
int attribTexCoords = glGetAttribLocation(program, "texCoords");
checkGlError();
int uniformTexture = glGetUniformLocation(program, "texture");
checkGlError();
glBindTexture(GL_TEXTURE_2D, texture);
checkGlError();
glUseProgram(program);
checkGlError();
glEnableVertexAttribArray(attribPosition);
checkGlError();
glEnableVertexAttribArray(attribTexCoords);
checkGlError();
glUniform1i(uniformTexture, texture);
checkGlError();
while (!mFinished) {
checkCurrent();
glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
checkGlError();
glClear(GL_COLOR_BUFFER_BIT);
checkGlError();
// drawQuad
triangleVertices.position(TRIANGLE_VERTICES_DATA_POS_OFFSET);
glVertexAttribPointer(attribPosition, 3, GL_FLOAT, false,
TRIANGLE_VERTICES_DATA_STRIDE_BYTES, triangleVertices);
triangleVertices.position(TRIANGLE_VERTICES_DATA_UV_OFFSET);
glVertexAttribPointer(attribTexCoords, 3, GL_FLOAT, false,
TRIANGLE_VERTICES_DATA_STRIDE_BYTES, triangleVertices);
glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
if (!mEgl.eglSwapBuffers(mEglDisplay, mEglSurface)) {
throw new RuntimeException("Cannot swap buffers");
}
checkEglError();
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
// Ignore
}
}
finishGL();
}
private int loadTexture(int resource) {
int[] textures = new int[1];
glActiveTexture(GL_TEXTURE0);
glGenTextures(1, textures, 0);
checkGlError();
int texture = textures[0];
glBindTexture(GL_TEXTURE_2D, texture);
checkGlError();
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
Bitmap bitmap = BitmapFactory.decodeResource(mResources, resource);
GLUtils.texImage2D(GL_TEXTURE_2D, 0, GL_RGBA, bitmap, GL_UNSIGNED_BYTE, 0);
checkGlError();
bitmap.recycle();
return texture;
}
private int buildProgram(String vertex, String fragment) {
int vertexShader = buildShader(vertex, GL_VERTEX_SHADER);
if (vertexShader == 0) return 0;
int fragmentShader = buildShader(fragment, GL_FRAGMENT_SHADER);
if (fragmentShader == 0) return 0;
int program = glCreateProgram();
glAttachShader(program, vertexShader);
checkGlError();
glAttachShader(program, fragmentShader);
checkGlError();
glLinkProgram(program);
checkGlError();
int[] status = new int[1];
glGetProgramiv(program, GL_LINK_STATUS, status, 0);
if (status[0] != GL_TRUE) {
String error = glGetProgramInfoLog(program);
Log.d(LOG_TAG, "Error while linking program:\n" + error);
glDeleteShader(vertexShader);
glDeleteShader(fragmentShader);
glDeleteProgram(program);
return 0;
}
return program;
}
private int buildShader(String source, int type) {
int shader = glCreateShader(type);
glShaderSource(shader, source);
checkGlError();
glCompileShader(shader);
checkGlError();
int[] status = new int[1];
glGetShaderiv(shader, GL_COMPILE_STATUS, status, 0);
if (status[0] != GL_TRUE) {
String error = glGetShaderInfoLog(shader);
Log.d(LOG_TAG, "Error while compiling shader:\n" + error);
glDeleteShader(shader);
return 0;
}
return shader;
}
private void checkEglError() {
int error = mEgl.eglGetError();
if (error != EGL10.EGL_SUCCESS) {
Log.w(LOG_TAG, "EGL error = 0x" + Integer.toHexString(error));
}
}
private void checkGlError() {
int error = glGetError();
if (error != GL_NO_ERROR) {
Log.w(LOG_TAG, "GL error = 0x" + Integer.toHexString(error));
}
}
private void finishGL() {
mEgl.eglDestroyContext(mEglDisplay, mEglContext);
mEgl.eglDestroySurface(mEglDisplay, mEglSurface);
}
private void checkCurrent() {
if (!mEglContext.equals(mEgl.eglGetCurrentContext()) ||
!mEglSurface.equals(mEgl.eglGetCurrentSurface(EGL10.EGL_DRAW))) {
if (!mEgl.eglMakeCurrent(mEglDisplay, mEglSurface, mEglSurface, mEglContext)) {
throw new RuntimeException("eglMakeCurrent failed "
+ GLUtils.getEGLErrorString(mEgl.eglGetError()));
}
}
}
private void initGL() {
mEgl = (EGL10) EGLContext.getEGL();
mEglDisplay = mEgl.eglGetDisplay(EGL10.EGL_DEFAULT_DISPLAY);
if (mEglDisplay == EGL10.EGL_NO_DISPLAY) {
throw new RuntimeException("eglGetDisplay failed "
+ GLUtils.getEGLErrorString(mEgl.eglGetError()));
}
int[] version = new int[2];
if (!mEgl.eglInitialize(mEglDisplay, version)) {
throw new RuntimeException("eglInitialize failed " +
GLUtils.getEGLErrorString(mEgl.eglGetError()));
}
mEglConfig = chooseEglConfig();
if (mEglConfig == null) {
throw new RuntimeException("eglConfig not initialized");
}
mEglContext = createContext(mEgl, mEglDisplay, mEglConfig);
mEglSurface = mEgl.eglCreateWindowSurface(mEglDisplay, mEglConfig, mSurface, null);
if (mEglSurface == null || mEglSurface == EGL10.EGL_NO_SURFACE) {
int error = mEgl.eglGetError();
if (error == EGL10.EGL_BAD_NATIVE_WINDOW) {
Log.e(LOG_TAG, "createWindowSurface returned EGL_BAD_NATIVE_WINDOW.");
return;
}
throw new RuntimeException("createWindowSurface failed "
+ GLUtils.getEGLErrorString(error));
}
if (!mEgl.eglMakeCurrent(mEglDisplay, mEglSurface, mEglSurface, mEglContext)) {
throw new RuntimeException("eglMakeCurrent failed "
+ GLUtils.getEGLErrorString(mEgl.eglGetError()));
}
mGL = mEglContext.getGL();
}
EGLContext createContext(EGL10 egl, EGLDisplay eglDisplay, EGLConfig eglConfig) {
int[] attrib_list = { EGL_CONTEXT_CLIENT_VERSION, 2, EGL10.EGL_NONE };
return egl.eglCreateContext(eglDisplay, eglConfig, EGL10.EGL_NO_CONTEXT, attrib_list);
}
private EGLConfig chooseEglConfig() {
int[] configsCount = new int[1];
EGLConfig[] configs = new EGLConfig[1];
int[] configSpec = getConfig();
if (!mEgl.eglChooseConfig(mEglDisplay, configSpec, configs, 1, configsCount)) {
throw new IllegalArgumentException("eglChooseConfig failed " +
GLUtils.getEGLErrorString(mEgl.eglGetError()));
} else if (configsCount[0] > 0) {
return configs[0];
}
return null;
}
private int[] getConfig() {
return new int[] {
EGL10.EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
EGL10.EGL_RED_SIZE, 8,
EGL10.EGL_GREEN_SIZE, 8,
EGL10.EGL_BLUE_SIZE, 8,
EGL10.EGL_ALPHA_SIZE, 8,
EGL10.EGL_DEPTH_SIZE, 0,
EGL10.EGL_STENCIL_SIZE, 0,
EGL10.EGL_NONE
};
}
void finish() {
mFinished = true;
}
}
您也可以使用NDK路线，这可能是从目标C更直接的过渡。