Thanks. I'm still a little confused about why there is a glActiveTexture and a glBindTexture. Seems like there ought to be one function for setting the current texture.
On Thursday, December 13, 2012 4:14:52 AM UTC-6, a1 wrote: > > > GLES20.glUniform1i(mTexSamplerHandle, 0); >> >> I would think it should be: >> >> GLES20.glUniform1i(mTexSamplerHandle, texId); >> >> But that doesn't work. >> >> Can someone help me understand this line? >> > > Each GPU has multiple texture units (at least 8 as required by GL ES 2.0 > specification), sampler2D (and other samplers type) are used to reference > texture unit in shader languages, therefore you set it to texture unit id > ordinal (unitId - GL_TEXTURE0), texture is bound on client side by > selecting texture unit, with call to glActiveTexture and then with > glBindTexture, which binds texture name to given sample type (eg. sampler2D > with GL_TEXTURE_2D) on currently selected texture unit. > > So to pass texture to shader you need to execute following sequence: > > GLES20.glActiveTexture(GL_TEXTURE0); // activate texture unit > GLES20.glBindTexture(GL_TEXTURE_2D, textureName); // bind texture to 2D > sampler on texture unit 0 > /* setup progam, states etc... */ > GLES20.glUniform1i(uniformLocationForSampler, 0); // pass texture unit > ordinal to shader > > -- > Bart > -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
