tree 334415ea3cf7882501ab9d30fb188f5d136f027c
parent fe88d2776746c733e1628c7ac9d9add9c9a280ed
author Elias Naur <elias.naur@gmail.com> 1536052969 +0200
committer Elias Naur <elias.naur@gmail.com> 1536360071 +0000

gl: add internalFormat to TexImage2D

The OpenGL C function glTexImage2D has the following signature:

void glTexImage2D(GLenum target,
 	GLint level,
 	GLint internalFormat,
 	GLsizei width,
 	GLsizei height,
 	GLint border,
 	GLenum format,
 	GLenum type,
 	const GLvoid * data);

However, the corresponding Context.TexImage2D method in package gl
does not include the internalFormat parameter, and use the format
argument instead. That's ok for many texture formats; for example,
RGBA textures have both format and internalFormat set to GL_RGBA.
But not always. In particular, OpenGL ES 3 allows the use of sRGB
encoded textures by specifying GL_SRGB8_ALPHA8 as internalFormat,
but keeping GL_RGBA as format.

Add the internalFormat to the Context package. This is unfortunately
a breaking change, but adding a new function ("glTexImage2D2"?) to
Context is too ugly for a parameter that should have been there all
along. (Adding a new method to the Context interface is technically
also a breaking change, but I don't expect that there are any
external implementers of the interface).

Change-Id: I12a45a34f604e51cb1be26aed906025ccfac533a
Reviewed-on: https://go-review.googlesource.com/133155
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>