[PATCH] opengl: Do not convert format with glTexImage2D on OpenGL ES

[PATCH] opengl: Do not convert format with glTexImage2D on OpenGL ES

[Akihiko Odaki]

OpenGL ES does not support conversion from the given data format
to the internal format with glTexImage2D.

Use the given data format as the internal format, and ignore
the given alpha channels with GL_TEXTURE_SWIZZLE_A in case the
format contains alpha channels.

Signed-off-by: Akihiko Odaki <akihiko.odaki@gmail.com>
---
 ui/console-gl.c | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/ui/console-gl.c b/ui/console-gl.c
index 0a6478161fe..7c9894a51d9 100644
--- a/ui/console-gl.c
+++ b/ui/console-gl.c
@@ -73,11 +73,20 @@ void surface_gl_create_texture(QemuGLShader *gls,
     glBindTexture(GL_TEXTURE_2D, surface->texture);
     glPixelStorei(GL_UNPACK_ROW_LENGTH_EXT,
                   surface_stride(surface) / surface_bytes_per_pixel(surface));
-    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB,
-                 surface_width(surface),
-                 surface_height(surface),
-                 0, surface->glformat, surface->gltype,
-                 surface_data(surface));
+    if (epoxy_is_desktop_gl()) {
+        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB,
+                     surface_width(surface),
+                     surface_height(surface),
+                     0, surface->glformat, surface->gltype,
+                     surface_data(surface));
+    } else {
+        glTexImage2D(GL_TEXTURE_2D, 0, surface->glformat,
+                     surface_width(surface),
+                     surface_height(surface),
+                     0, surface->glformat, surface->gltype,
+                     surface_data(surface));
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_SWIZZLE_A, GL_ONE);
+    }
 
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
-- 
2.24.3 (Apple Git-128)

Re: [PATCH] opengl: Do not convert format with glTexImage2D on OpenGL ES

[Gerd Hoffmann]

On Fri, Feb 19, 2021 at 06:48:03PM +0900, Akihiko Odaki wrote:
> OpenGL ES does not support conversion from the given data format
> to the internal format with glTexImage2D.
> 
> Use the given data format as the internal format, and ignore
> the given alpha channels with GL_TEXTURE_SWIZZLE_A in case the
> format contains alpha channels.

Hmm.  Do you know what effect this has performance-wise?
Is it maybe useful to not convert for desktop gl too?

take care,
  Gerd

Re: [PATCH] opengl: Do not convert format with glTexImage2D on OpenGL ES

[Akihiko Odaki]

2021年2月19日(金) 23:14 Gerd Hoffmann <kraxel@redhat.com>:
>
> On Fri, Feb 19, 2021 at 06:48:03PM +0900, Akihiko Odaki wrote:
> > OpenGL ES does not support conversion from the given data format
> > to the internal format with glTexImage2D.
> >
> > Use the given data format as the internal format, and ignore
> > the given alpha channels with GL_TEXTURE_SWIZZLE_A in case the
> > format contains alpha channels.
>
> Hmm.  Do you know what effect this has performance-wise?
> Is it maybe useful to not convert for desktop gl too?

I have no idea about performance, but I am concerned about
compatibility. OpenGL 4.6 core profile does not support GL_BGRA, which
is aliased as GL_BGRA_EXT by epoxy, as internalformat. I also tested
with Intel HD Graphics 3000/Mesa 20.3.4 but it didn't work.

>
> take care,
>   Gerd
>

Re: [PATCH] opengl: Do not convert format with glTexImage2D on OpenGL ES

[Gerd Hoffmann]

On Fri, Feb 19, 2021 at 06:48:03PM +0900, Akihiko Odaki wrote:
> OpenGL ES does not support conversion from the given data format
> to the internal format with glTexImage2D.
> 
> Use the given data format as the internal format, and ignore
> the given alpha channels with GL_TEXTURE_SWIZZLE_A in case the
> format contains alpha channels.
> 
> Signed-off-by: Akihiko Odaki <akihiko.odaki@gmail.com>

Added to UI patch queue.

thanks,
  Gerd