How to create offscreen Texture and use it on Android with OpenGL ES 2 -

How to create offscreen Texture and use it on Android with OpenGL ES 2 -

i new in opengl.

how can create offscreen texture, can informations of (e.g. pixelcolor clicking on view texture) ?

i tried many many things illustration fbo, did't work. have no imagination how load bitmap offscreen texture , info of it. frustated :/

edit: took this tutorial example, don't know if fits problem. createframebuffer

public void createframebuffer(gl10 gl) { floatbuffer uvbuffer2; int texture[] = new int[1]; gles20.glgentextures(1, texture, 0); gles20.glbindtexture(gles20.gl_texture0, texture[0]); float uvs2[] = { 0.0f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f, 1.0f, 0.0f }; bytebuffer bb = bytebuffer.allocatedirect(uvs2.length * 4); bb.order(byteorder.nativeorder()); uvbuffer2 = bb.asfloatbuffer(); uvbuffer2.put(uvs2); uvbuffer2.position(0); gl.gltexcoordpointer(2, gles20.gl_byte, 0, uvbuffer2); //load image int idtest = mcontext.getresources().getidentifier("drawable/testgroesse", null, mcontext.getpackagename()); bitmap wood = bitmapfactory.decoderesource(mcontext.getresources(), idtest); gles20.gltexparameterf(gles20.gl_texture0, gles20.gl_texture_min_filter, gles20.gl_linear); gles20.gltexparameterf(gles20.gl_texture0, gles20.gl_texture_mag_filter, gles20.gl_linear); glutils.teximage2d(gles20.gl_texture0, 0, wood, 0); gles20.glenable(gles20.gl_texture0); gl.glenableclientstate(gles20.gl_texture0); //color picking background start bytebuffer bytepickedcolor = bytebuffer.allocate(4); bytepickedcolor.order(byteorder.nativeorder()); gles20.glflush(); gles20.glreadpixels(touchxint, touchyint, 1, 1, gles20.gl_rgba, gles20.gl_unsigned_byte, bytepickedcolor); byte b[] = new byte[4]; bytepickedcolor.get(b); string key = "" + b[0] + " " + b[1] + " " + b[2] + " " + b[3]; log.d("color_farbe: ", key); bytepickedcolor.rewind(); //color picking background end }

to oversimplify:

the fbo created buffer contains rgba + 16-bit depth. attaching texture can reuse texture have same rgba info fbo. @ origin buffer still empty, still need clear , draw other render buffer.

so set image/texture on buffer need create texture (with image) , draw textured rectangle on fbo.

it seem not after:

"how can create offscreen texture?" onscreen texture? textures offscreen. "get informations of it"? of what, texture?! there 2 ways of creating texture: first image in case rather lookup texel source image. sec drawing fbo procedure need read pixels (try glreadpixels). "e.g. pixelcolor clicking on view texture" clicking on what?! can click on view/screen not texture. if 1 time again need sample of rendered view see before need read pixels described before.

it looks looking glreadpixels colour values current buffer. if not case please rephrase question , explain goal here.

android opengl-es