vo_opengl: make PBOs work on GLES 3.x

For some reason, GLES has no glMapBuffer, only glMapBufferRange.

GLES 2 has no buffer mapping at all, and GL 2.1 does not always have
glMapBufferRange. On those PBOs remain unsupported (there's no reason to
care about GL 2.1 without the extension).

This doesn't actually work on ANGLE, and I have no idea why. (There are
artifacts on OSD, as if parts of the OSD data weren't copied.) It works
on desktop OpenGL and at least 1 other ES 3 implementation. Don't enable
it on ANGLE, I guess.

1 files changed, 5 insertions, 4 deletions

diff --git a/video/out/opengl/osd.c b/video/out/opengl/osd.c
index bf03d34e90..d8059166be 100644
--- a/video/out/opengl/osd.c
+++ b/video/out/opengl/osd.c
@@ -139,18 +139,19 @@ static bool upload_pbo(struct mpgl_osd *ctx, struct mpgl_osd_part *osd,
     GL *gl = ctx->gl;
     bool success = true;
     const struct gl_format *fmt = ctx->fmt_table[imgs->format];
-    int pix_stride = gl_bytes_per_pixel(fmt->format, fmt->type);
+    size_t pix_stride = gl_bytes_per_pixel(fmt->format, fmt->type);
+    size_t buffer_size = pix_stride * osd->h * osd->w;
 
     if (!osd->buffer) {
         gl->GenBuffers(1, &osd->buffer);
         gl->BindBuffer(GL_PIXEL_UNPACK_BUFFER, osd->buffer);
-        gl->BufferData(GL_PIXEL_UNPACK_BUFFER, osd->w * osd->h * pix_stride,
-                        NULL, GL_DYNAMIC_COPY);
+        gl->BufferData(GL_PIXEL_UNPACK_BUFFER, buffer_size, NULL, GL_DYNAMIC_COPY);
         gl->BindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
     }
 
     gl->BindBuffer(GL_PIXEL_UNPACK_BUFFER, osd->buffer);
-    char *data = gl->MapBuffer(GL_PIXEL_UNPACK_BUFFER, GL_WRITE_ONLY);
+    char *data = gl->MapBufferRange(GL_PIXEL_UNPACK_BUFFER, 0, buffer_size,
+                                    GL_MAP_WRITE_BIT | GL_MAP_INVALIDATE_BUFFER_BIT);
     if (!data) {
         success = false;
     } else {