On OpenGL ES 2 core implementation, only GL_CLAMP_TO_EDGE parameter is supported as wrap mode for NPOT (non-power of two dimensions) textures. Initially, wrap modes are set to GL_REPEAT.

An extension OES_texture_npot (Available on most of the modern platform), however, adds the support of other GL_REPEAT and GL_MIRRORED_REPEAT to the wrap modes. But this extension may not be present on every target.

On such platforms, because the texture might be inconsistent, we may get an unexpected result.