For text that only changes slowly (so you aren’t continually reloading the texture) that can be blindingly efficient. The OpenGL ES APIs provided by the Android framework offers a set of tools for displaying high-end, animated graphics that are limited only by your imagination and can also benefit from the acceleration of graphics processing units (GPUs) provided on many Android devices. On systems with decent shader support, I’ve been experimenting with a technique where I send the strings I need down to the GPU as a texture map with one texel per character (containing the ASCII code) and use fragment shader code to convert use that value as the coordinate for looking up the font texture - amazingly, it actually works pretty well. Another approach (if your text is relatively fixed) is to store entire words, phrases or even sentences as texture and draw the whole thing with one textured quad.Ī very long time ago, I wrote a FAQ about this (that was back in the era of OpenGL 1.2!) ()

If you have a lot of text - that might mean drawing a LOT of polygons. One simple way to do that is to make up a short/wide texture map with all of the ASCII characters in it - then write code to draw each letter as a textured quadrilateral using the appropriate texture coordinates to extract the right letter out of the texture map. You either do that outside of the API (maybe using some other operating-system commands) - or you write your own font rendering stuff. If you are porting a game from the iOS or Android platforms, you have probably made a significant investment in OpenGL ES 2.0. n.n.n refers to sections and tables in the OpenGL. The interface consists of a set of procedures and functions that allow a programmer to specify the objects and operations involved in producing high-quality graphical images, specifically color images of three-dimensional objects. There is no API in OpenGL (or OpenGLES) for drawing text. OpenGL ES is a software interface to graphics hardware.

Opengl 2.0 es