vo_opengl: move FBO helper to gl_utils

This is somewhat messy, because fbotex_init() itself was depending on
some gl_video parameters unrelated to FBO creation (like what scaler was
in use - what the fuck did this check do in this function?), so this
commit does a bit more than moving code around. In particular, the FBO
for the separate scaling intermediate step now always uses GL_NEAREST
sampling, and all FBOs are destroyed/recreated on renderer
reinitialization.

This also moves the function matrix_ortho2d() - trivial enough not to
put it into a separate commit.

1 files changed, 14 insertions, 0 deletions

diff --git a/video/out/gl_utils.h b/video/out/gl_utils.h
index 482c88a0fa..514b873dbe 100644
--- a/video/out/gl_utils.h
+++ b/video/out/gl_utils.h
@@ -66,4 +66,18 @@ void gl_vao_bind(struct gl_vao *vao);
 void gl_vao_unbind(struct gl_vao *vao);
 void gl_vao_bind_attribs(struct gl_vao *vao, GLuint program);
 
+struct fbotex {
+    GL *gl;
+    GLuint fbo;
+    GLuint texture;
+    int tex_w, tex_h;           // size of .texture
+    int vp_x, vp_y, vp_w, vp_h; // viewport of fbo / used part of the texture
+};
+
+bool fbotex_init(struct fbotex *fbo, GL *gl, struct mp_log *log, int w, int h,
+                 GLenum gl_target, GLenum gl_filter, GLenum iformat);
+void fbotex_uninit(struct fbotex *fbo);
+
+void gl_matrix_ortho2d(float m[3][3], float x0, float x1, float y0, float y1);
+
 #endif