configure: Improve OpenGL dependency detections

This has the following visible changes:

- GBM is required only for OpenGL dma-buf.
- X11 is explicitly required by gtk-egl.
- EGL is now mandatory for the OpenGL displays.

The last one needs some detailed description. Before this change,
EGL was tested only for OpenGL dma-buf with the check of
EGL_MESA_image_dma_buf_export. However, all of the OpenGL
displays depend on EGL and EGL_MESA_image_dma_buf_export is always
defined by epoxy's EGL interface.
Therefore, it makes more sense to always check the presence of EGL
and say the OpenGL displays are available along with OpenGL dma-buf
if it is present.

Signed-off-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Message-Id: <20210223060307.87736-1-akihiko.odaki@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

1 files changed, 15 insertions, 22 deletions

diff --git a/configure b/configure
index a79b3746d4..b922d1ea26 100755
--- a/configure
+++ b/configure
@@ -394,7 +394,6 @@ u2f="auto"
 libusb="$default_feature"
 usb_redir="$default_feature"
 opengl="$default_feature"
-opengl_dmabuf="no"
 cpuid_h="no"
 avx2_opt="$default_feature"
 capstone="auto"
@@ -3607,14 +3606,24 @@ if $pkg_config gbm; then
 fi
 
 if test "$opengl" != "no" ; then
-  opengl_pkgs="epoxy gbm"
-  if $pkg_config $opengl_pkgs; then
-    opengl_cflags="$($pkg_config --cflags $opengl_pkgs)"
-    opengl_libs="$($pkg_config --libs $opengl_pkgs)"
+  epoxy=no
+  if $pkg_config epoxy; then
+    cat > $TMPC << EOF
+#include <epoxy/egl.h>
+int main(void) { return 0; }
+EOF
+    if compile_prog "" "" ; then
+      epoxy=yes
+    fi
+  fi
+
+  if test "$epoxy" = "yes" ; then
+    opengl_cflags="$($pkg_config --cflags epoxy)"
+    opengl_libs="$($pkg_config --libs epoxy)"
     opengl=yes
   else
     if test "$opengl" = "yes" ; then
-      feature_not_found "opengl" "Please install opengl (mesa) devel pkgs: $opengl_pkgs"
+      feature_not_found "opengl" "Please install epoxy with EGL"
     fi
     opengl_cflags=""
     opengl_libs=""
@@ -3622,19 +3631,6 @@ if test "$opengl" != "no" ; then
   fi
 fi
 
-if test "$opengl" = "yes"; then
-  cat > $TMPC << EOF
-#include <epoxy/egl.h>
-#ifndef EGL_MESA_image_dma_buf_export
-# error mesa/epoxy lacks support for dmabufs (mesa 10.6+)
-#endif
-int main(void) { return 0; }
-EOF
-  if compile_prog "" "" ; then
-    opengl_dmabuf=yes
-  fi
-fi
-
 ##########################################
 # libxml2 probe
 if test "$libxml2" != "no" ; then
@@ -5837,9 +5833,6 @@ if test "$opengl" = "yes" ; then
   echo "CONFIG_OPENGL=y" >> $config_host_mak
   echo "OPENGL_CFLAGS=$opengl_cflags" >> $config_host_mak
   echo "OPENGL_LIBS=$opengl_libs" >> $config_host_mak
-  if test "$opengl_dmabuf" = "yes" ; then
-    echo "CONFIG_OPENGL_DMABUF=y" >> $config_host_mak
-  fi
 fi
 
 if test "$gbm" = "yes" ; then