This is just to share something that took me a long time to figure out. If you don't need your Depthbuffer or don't have a Depth Buffer Attachment Point setup in EGL this might help.
For some reason I couldn't get rendering to texture to work setting the render buffer object RBO to depth buffer: like so
GLES20.glFramebufferTexture2D(GLES20.GL_FRAMEBUFFER,
GLES20.GL_COLOR_ATTACHMENT0, GLES20.GL_TEXTURE_2D,
juliaTex[0], 0);
rain.checkGlError("glFramebufferTexture2D");
GLES20.glFramebufferRenderbuffer(GLES20.GL_FRAMEBUFFER,
GLES20.GL_DEPTH_ATTACHMENT, GLES20.GL_RENDERBUFFER,
juliaRBO[0]);
rain.checkGlError("glFramebufferRenderbuffer");
int status = GLES20.glCheckFramebufferStatus(GLES20.GL_FRAMEBUFFER);
Causes error status == GLES20.GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT
If I change render buffer storage to GLES20.GL_RGBA4, as opposed to GLES20.DEPTH_COMPONENT16 and change GLES20.GL_DEPTH_ATTACHMENT to GLES20.GL_COLOR_ATTACHMENT0 then the error goes away,
Change this
// create render buffer and bind 16-bit depth buffer
GLES20.glBindRenderbuffer(GLES20.GL_RENDERBUFFER, juliaRBO[0]);
rain.checkGlError("glBindRenderBuffer");
GLES20.glRenderbufferStorage(GLES20.GL_RENDERBUFFER, GLES20.DEPTH_COMPONENT16,
rain.width, rain.height);
to this
// create render buffer and bind 16-bit depth buffer
GLES20.glBindRenderbuffer(GLES20.GL_RENDERBUFFER, juliaRBO[0]);
rain.checkGlError("glBindRenderBuffer");
GLES20.glRenderbufferStorage(GLES20.GL_RENDERBUFFER, GLES20.GL_RGBA4,
rain.width, rain.height);
And the original code to this:
GLES20.glFramebufferTexture2D(GLES20.GL_FRAMEBUFFER,
GLES20.GL_COLOR_ATTACHMENT0, GLES20.GL_TEXTURE_2D,
juliaTex[0], 0);
rain.checkGlError("glFramebufferTexture2D");
GLES20.glFramebufferRenderbuffer(GLES20.GL_FRAMEBUFFER,
GLES20.GL_COLOR_ATTACHMENT0, GLES20.GL_RENDERBUFFER,
juliaRBO[0]);
rain.checkGlError("glFramebufferRenderbuffer");
then status == GLES20.GL_FRAMEBUFFER_COMPLETE
But the texture is empty.
here is the call to create storage texture
// bind texture
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, juliaTex[0]);
// clamp texture to edges
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_S,
GLES20.GL_CLAMP_TO_EDGE);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_T,
GLES20.GL_CLAMP_TO_EDGE);
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);
rain.checkGlError("glTexParameter JuliaTex");
// create it
/*
int[] buf = new int[rain.width * rain.height];
juliaTexBuff = ByteBuffer.allocateDirect(buf.length
* rain.FLOAT_SIZE_BYTES).order(ByteOrder.nativeOrder()).asIntBuffer();
*/
// generate the textures
GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_RGBA,
rain.width, rain.height, 0, GLES20.GL_RGBA,
GLES20.GL_UNSIGNED_SHORT_4_4_4_4, null);
To get this to work in addition to attaching the render buffer to the color attachment point I swapped the order of the Framebuffer attachments:
GLES20.glFramebufferRenderbuffer(GLES20.GL_FRAMEBUFFER,
GLES20.GL_COLOR_ATTACHMENT0, GLES20.GL_RENDERBUFFER,
juliaRBO[0]);
rain.checkGlError("glFramebufferRenderbuffer");
GLES20.glFramebufferTexture2D(GLES20.GL_FRAMEBUFFER,
GLES20.GL_COLOR_ATTACHMENT0, GLES20.GL_TEXTURE_2D,
juliaTex[0], 0);
rain.checkGlError("glFramebufferTexture2D");
So that Texture2D is attached to the Framebuffer color layer after Renderbuffer. I assume the last connection point is the point OpenGL ES uses.
Related
I am using following method to create OpenGL ES texture on android.
private int createTexture(int width, int height, int i) {
int[] mTextureHandles = new int[1];
GLES20.glGenTextures(1, mTextureHandles, 0);
int textureID = mTextureHandles[0];
GLES20.glActiveTexture(GLES20.GL_TEXTURE0 + i);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, textureID);
GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_RGBA, width, height, 0, GLES20.GL_RGBA, GLES20.GL_UNSIGNED_BYTE, null);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_S, GLES20.GL_CLAMP_TO_EDGE);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_T, GLES20.GL_REPEAT);
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);
return textureID;
}
Then uploading a bitmap to this texture and simply rendering it using GLSurfaceView's Renderer.
Most of the times it is working as expected,
But randomly the texture is displayed like this. (here GL_TEXTURE_WRAP_S mode is GLES20.GL_CLAMP_TO_EDGE
After changing wrap mode.
If GL_TEXTURE_WRAP_S = GLES20.GL_REPEAT then (again randomly) texture is displayed like this(notice the color change).
I have already tried using power of 2 texture.
Code for vertex buffer
private FloatBuffer createVertexBuffer(RectF glCoords) {
// RectF glCoords contains gl vertices.
// current Rect read from Logcat.
// left = -0.5833333, top = 0.5, right = 0.5833334, bottom = -0.5
float[] vertices = new float[]{glCoords.left, glCoords.top, 0, 1, // V1 - top left
glCoords.left, glCoords.bottom, 0, 1, // V2 - bottom left
glCoords.right, glCoords.bottom, 0, 1, // V3 - bottom right
glCoords.right, glCoords.top, 0, 1 // V4 - top right
};
FloatBuffer vBuffer = ByteBuffer.allocateDirect(vertices.length * bytesPerFloat)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
vBuffer.put(vertices);
vBuffer.position(0);
return vBuffer;
}
IndicesBuffer is not used as I am using Triangle-Fan to render triangles.
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_FAN, 0, 6);
It would be really helpful if someone can point out as to what could be causing this
Your geometry seems to be a 4-vertex rectangle (quad), but the code wants to draw a fan with 6 vertices - GLES20.glDrawArrays(GLES20.GL_TRIANGLE_FAN, 0, 6);
Those extra 2 vertices aren't initialized, not specified in the vertex array. OpenGL will read beyond the defined part of the array. The results would be random, and I'd even expect crashes.
Replace 6 with 4 in glDrawArrays() call, this should fix the problem.
I am new to OpenGL, work on Android. Found good code example in Web with possibility to record everything. But I found one big problem: depth test doesn't work, so in my models all faces that opposite to camera are lighted even if they are behind another faces:
I think some mistakes could be in this part of code:
/**
* Prepares the off-screen framebuffer.
*/
private void prepareFramebuffer(int width, int height) {
GlUtil.checkGlError("prepareFramebuffer start");
int[] values = new int[1];
// Create a texture object and bind it. This will be the color buffer.
GLES20.glGenTextures(1, values, 0);
GlUtil.checkGlError("glGenTextures");
mOffscreenTexture = values[0]; // expected > 0
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mOffscreenTexture);
GlUtil.checkGlError("glBindTexture " + mOffscreenTexture);
// Create texture storage.
GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_RGBA, width, height, 0,
GLES20.GL_RGBA, GLES20.GL_UNSIGNED_BYTE, null);
// Set parameters. We're probably using non-power-of-two dimensions, so
// some values may not be available for use.
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER,
GLES20.GL_NEAREST);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER,
GLES20.GL_LINEAR);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_S,
GLES20.GL_CLAMP_TO_EDGE);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_T,
GLES20.GL_CLAMP_TO_EDGE);
GlUtil.checkGlError("glTexParameter");
// Create framebuffer object and bind it.
GLES20.glGenFramebuffers(1, values, 0);
GlUtil.checkGlError("glGenFramebuffers");
mFramebuffer = values[0]; // expected > 0
GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, mFramebuffer);
GlUtil.checkGlError("glBindFramebuffer " + mFramebuffer);
// Create a depth buffer and bind it.
GLES20.glGenRenderbuffers(1, values, 0);
GlUtil.checkGlError("glGenRenderbuffers");
mDepthBuffer = values[0]; // expected > 0
GLES20.glBindRenderbuffer(GLES20.GL_RENDERBUFFER, mDepthBuffer);
GlUtil.checkGlError("glBindRenderbuffer " + mDepthBuffer);
// Allocate storage for the depth buffer.
GLES20.glRenderbufferStorage(GLES20.GL_RENDERBUFFER, GLES20.GL_DEPTH_COMPONENT16,
width, height);
GlUtil.checkGlError("glRenderbufferStorage");
// Attach the depth buffer and the texture (color buffer) to the framebuffer object.
GLES20.glFramebufferRenderbuffer(GLES20.GL_FRAMEBUFFER, GLES20.GL_DEPTH_ATTACHMENT,
GLES20.GL_RENDERBUFFER, mDepthBuffer);
GlUtil.checkGlError("glFramebufferRenderbuffer");
GLES20.glFramebufferTexture2D(GLES20.GL_FRAMEBUFFER, GLES20.GL_COLOR_ATTACHMENT0,
GLES20.GL_TEXTURE_2D, mOffscreenTexture, 0);
GlUtil.checkGlError("glFramebufferTexture2D");
// See if GLES is happy with all this.
int status = GLES20.glCheckFramebufferStatus(GLES20.GL_FRAMEBUFFER);
if (status != GLES20.GL_FRAMEBUFFER_COMPLETE) {
// throw new RuntimeException("Framebuffer not complete, status=" + status);
}
// Switch back to the default framebuffer.
GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, 0);
GlUtil.checkGlError("prepareFramebuffer done");
}
Another important things that I have already done:
/**
* Prepares window surface and GL state.
*/
private void prepareGl(Surface surface) {
Log.d(TAG, "prepareGl");
EglCore.logCurrent("before creating");
GlUtil.checkGlError("debug");
if (mWindowSurface == null)
mWindowSurface = new WindowSurface(mEglCore, surface, false);
mWindowSurface.makeCurrent();
EglCore.logCurrent("after creation");
glClearColor(0f, 0f, 0f, 1f); //glClearColor(0.15f, 0.15f, 0.15f, 1f);
GlUtil.checkGlError("debug");
glEnable(GL_DEPTH_TEST);
GlUtil.checkGlError("debug");
glEnable(GL_CULL_FACE);
GlUtil.checkGlError("debug");
glCullFace(GL_BACK);
GlUtil.checkGlError("debug");
glShadeModel(GL_SMOOTH);
GlUtil.checkGlError("debug");
glEnable(GL_BLEND);
GlUtil.checkGlError("debug");
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
What am I doing wrong? Where can be the mistake?
Add onDraw code:
private void draw() {
GlUtil.checkGlError("draw start");
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glDepthFunc(GL_LESS);
if (leftEye != null) {
resetMatrices();
setModelViewMatrix();
translateMEyes();
eyeTextureProgram.useProgram();
eyeTextureProgram.setViewAndTexture(modelViewProjectionMatrix, textureEye);
setProgramParams(eyeTextureProgram, textureEye);
leftEye.bindData(eyeTextureProgram);
leftEye.draw();
}
if (rightEye != null) {
rightEye.bindData(eyeTextureProgram);
rightEye.draw();
}
glDepthFunc(GL_LEQUAL);
resetMatrices();
setModelViewMatrix();
setProgramParams(faceTextureProgram, textureFace);
headBase.bindData(faceTextureProgram);
headBase.draw();
GlUtil.checkGlError("draw done");
}
Set the clearing value of the depth buffer to 1.0. Clearing value of the depth buffer should be the max value of the depth range which by default is 0.0 - 1.0.
glClearDepth(1.0)
Also, ensure that you clear both the depth and color buffer before your drawing.
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
Im implementing Render to texture Using FBOs in android, as first step im creating a texture, but i get error 1280 by calling GLES20.glGenTextures method.
the Texture Creator function is bellow:
public int CreateTexture(int w, int h){
final int[] textureId = new int[1];
int i;
//ijad mikonim 1 Adad texturte ro rooye textureID
GLES20.glGenTextures(1, textureId,0);
i = GLES20.glGetError();
//BindTexture miad texturo ro baraaye call shodan amaade mikone
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, textureId[0]);
//texture nahaE ro ijaad mikonim
GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_RGBA, w, h, 0, GLES20.GL_RGBA, GLES20.GL_FLOAT, null);
//in null tooye voroodie akharie bala, mige ke fazaa ro baraye texture ijad kon vali ba hichi poresh nakon hanooz
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_NEAREST);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_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);
if(i!=0){
Log.d("ERROR", "ERROR Happend"+i+"");
return i;
}
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, 0);
return textureId[0];
}
when i call this method it returns error 1280.
You got a GL_INVALID_ENUM error, which means you passed an unsupported enum value to a GL function. error is not in CreateTexture function , it is probably in function call before CreateTexture or in your opengl init function
I develop video app on Android and use OpenGL for render and filtering video from camera via shaders. One of my shaders use two textures - one is live frame from camera and another is the previous render pass result. So I need to render picture twice - to screen for preview and to separate Texture for next render pass. To achieve it I use Frame Buffer object. Here is my code:
For init frame buffer:
private void initPredrawBuffer() {
GLES20.glActiveTexture(GLES20.GL_TEXTURE1);
prevBuffer = new int[1];
GLES20.glGenFramebuffers(1, prevBuffer, 0);
GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, prevBuffer[0]);
prevTexture = new int[1];
GLES20.glGenTextures(1, prevTexture, 0);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, prevTexture[0]);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER,
GLES20.GL_NEAREST);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER,
GLES20.GL_LINEAR);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_S,
GLES20.GL_CLAMP_TO_EDGE);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_T,
GLES20.GL_CLAMP_TO_EDGE);
GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_RGBA, mFrameWidth, mFrameHeight, 0, GLES20.GL_RGBA, GLES20.GL_UNSIGNED_BYTE, null);
GLES20.glFramebufferTexture2D(GLES20.GL_FRAMEBUFFER, GLES20.GL_COLOR_ATTACHMENT0, GLES20.GL_TEXTURE_2D, prevTexture[0], 0);
int[] depthRenderbuffers = new int[1];
GLES20.glGenRenderbuffers(1, depthRenderbuffers, 0);
GLES20.glBindRenderbuffer(GLES20.GL_RENDERBUFFER, depthRenderbuffers[0]);
GLES20.glRenderbufferStorage(GLES20.GL_RENDERBUFFER, GLES20.GL_DEPTH_COMPONENT16, mFrameWidth, mFrameHeight);
GLES20.glFramebufferRenderbuffer(GLES20.GL_FRAMEBUFFER, GLES20.GL_DEPTH_ATTACHMENT, GLES20.GL_RENDERBUFFER, depthRenderbuffers[0]);
int status = GLES20.glCheckFramebufferStatus(GLES20.GL_FRAMEBUFFER);
if (status != GLES20.GL_FRAMEBUFFER_COMPLETE) {
throw new RuntimeException("Incomplete buffer");
}
}
and for render:
private void draw(boolean offScreen, float[] mvpMatrix, FloatBuffer vertexBuffer, int firstVertex,
int vertexCount, int coordsPerVertex, int vertexStride,
float[] texMatrix, FloatBuffer texBuffer, int textureId, int texStride) {
GlUtil.checkGlError("draw start");
if (offScreen)
GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, prevBuffer[0]);
else
GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, 0);
// Select the program.
GLES20.glUseProgram(firstFrame && firstFrameProgram > 0 ? firstFrameProgram : mProgramHandle);
GlUtil.checkGlError("glUseProgram");
// Set the texture.
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLES20.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, textureId);
// Copy the model / view / projection matrix over.
GLES20.glUniformMatrix4fv(muMVPMatrixLoc, 1, false, mvpMatrix, 0);
GlUtil.checkGlError("glUniformMatrix4fv");
// Copy the texture transformation matrix over.
GLES20.glUniformMatrix4fv(muTexMatrixLoc, 1, false, texMatrix, 0);
GlUtil.checkGlError("glUniformMatrix4fv");
// Enable the "aPosition" vertex attribute.
GLES20.glEnableVertexAttribArray(maPositionLoc);
GlUtil.checkGlError("glEnableVertexAttribArray");
// Connect vertexBuffer to "aPosition".
GLES20.glVertexAttribPointer(maPositionLoc, coordsPerVertex,
GLES20.GL_FLOAT, false, vertexStride, vertexBuffer);
GlUtil.checkGlError("glVertexAttribPointer");
// Enable the "aTextureCoord" vertex attribute.
GLES20.glEnableVertexAttribArray(maTextureCoordLoc);
GlUtil.checkGlError("glEnableVertexAttribArray");
// Connect texBuffer to "aTextureCoord".
GLES20.glVertexAttribPointer(maTextureCoordLoc, 2,
GLES20.GL_FLOAT, false, texStride, texBuffer);
GlUtil.checkGlError("glVertexAttribPointer");
// Setting Light Trails filter params
if (mProgramType == ProgramType.TEXTURE_LIGHT_TRAILS && !firstFrame) {
GLES20.glUniform1i(muTextureNew, 0);
GlUtil.checkGlError("glUniform1i muTextureNew");
GLES20.glActiveTexture(GLES20.GL_TEXTURE1);
GlUtil.checkGlError("temp glActiveTexture");
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, prevTexture[0]);
GlUtil.checkGlError("temp glBindTexture");
GLES20.glUniform1i(muTexturePrev, 1);
GlUtil.checkGlError("glUniform1i muTexturePrev");
GLES20.glUniform1f(muLightTrailsExposure, lightTrailsKernel[0]);
GlUtil.checkGlError("glUniform1f muLightTrailsExposure");
GLES20.glUniform1f(muLightTrailsEcho, lightTrailsKernel[1]);
GlUtil.checkGlError("glUniform1f muLightTrailsEcho");
GLES20.glUniform1f(muLightTrailsLimit, lightTrailsKernel[2]);
GlUtil.checkGlError("glUniform1f muLightTrailsLimit");
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GlUtil.checkGlError("temp glActiveTexture");
}
// Draw the rect.
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, firstVertex, vertexCount);
GlUtil.checkGlError("glDrawArrays");
GLES20.glFinish();
}
The problem is that render to frame buffer not working, and glReadPixels always return an empty array. Render to screen works fine.
I am rendering to a frame buffer, and then I want to use that as a texture.
I can save the frame buffer to a file using glReadPixels so I am sure that I am rendering OK.
I can bind to fixed texture and render that OK.
But I cannot bind to the frame buffer to render that in place of the fixed texture.
//setup:
private void setupRenderToTexture() {
fb = new int[numberOfBuffers];
depthRb = new int[numberOfBuffers];
renderTex = new int[numberOfBuffers];
texBuffer = new IntBuffer[numberOfBuffers];
// generate
GLES20.glGenFramebuffers(fb.length, fb, 0);
GLES20.glGenRenderbuffers(depthRb.length, depthRb, 0);
GLES20.glGenTextures(renderTex.length, renderTex, 0);
GLErrorHandler.checkGlError("glGenFramebuffers");
for (int i = 0; i < fb.length; i++) {
GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, fb[i]);
// generate color texture
GLState.Instance.bindTexture(0, renderTex[i]);
// parameters
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D,
// GLES20.GL_TEXTURE_WRAP_S, GLES20.GL_CLAMP_TO_EDGE);
GLES20.GL_TEXTURE_WRAP_S, GLES20.GL_REPEAT);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D,
// GLES20.GL_TEXTURE_WRAP_T, GLES20.GL_CLAMP_TO_EDGE);
GLES20.GL_TEXTURE_WRAP_T, GLES20.GL_REPEAT);
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);
// create it
// create an empty intbuffer first?
int[] fileData = new int[width * height];
texBuffer[i] = IntBuffer.wrap(fileData);
GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_RGBA, width,
height, 0, GLES20.GL_RGBA, GLES20.GL_UNSIGNED_BYTE,
texBuffer[i]);
GLES20.glFramebufferTexture2D(GLES20.GL_FRAMEBUFFER, GLES20.GL_COLOR_ATTACHMENT0, GLES20.GL_TEXTURE_2D,
renderTex[i], 0);
// create render buffer and bind 16-bit depth buffer
GLES20.glBindRenderbuffer(GLES20.GL_RENDERBUFFER, depthRb[i]);
GLES20.glRenderbufferStorage(GLES20.GL_RENDERBUFFER,
GLES20.GL_DEPTH_COMPONENT16, width, height);
GLErrorHandler.checkGlError("glRenderbufferStorage or above");
}
GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, 0);
}
Use the frame buffer:
GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, fb[0]);
Save the frame buffer (for testing):
GLES20.glReadPixels(sourceX, sourceY, width, height, GL10.GL_RGBA,
GL10.GL_UNSIGNED_BYTE, ib);
Then to render to screen:
GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, 0);
GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, fb[0]);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, texture); //some simple texture works but:
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, renderTex[0]); //frame buffer texture does not work
All I get is a black screen if I bind to renderTex[0]
You are mis-using the FBO. You have to attach an empty texture so that it can render into it.
See this page