As I noted there's no support from Ogles 2.0 for all the required transformation matrices. I've written a ogles 1.x engine before, now I wan't to extend that engine so that it supports shaders too. For now everything works fine, but now I have some questions about ogles 2.0:
- what matrices I have to offer my users as uniforms? I'm sure I have to support the projection matrix and the modelview matrix, but are there more that should be supported? I.e I don't know if I sould offer the modelview matix as the camera matrix and the object-to-world matrix or if it is suffident to offer the already complete modelview matrix
- for my first prototype I simply used OpenGl ES 1.x simply to create the matrix stuff this way: for each node in the graph I let ogles 1.0 calulate the modelview matrix just with glrotate, gltranslate and glscale. Then I grab that matrix and offer it as uniform to the shader of that node. That works for sure, but are there any issues with this method(I.e may there me problems by using ogles 1 for the transformation and ogles 2 for the rendering, may this be bad for performance if the gpu has to switch between ogles 1 and 2)?
Thanks for your reply!