[Spice-devel] [PATCHv2 3/3] egl: set current context, fix multiple display

[Marc-André Lureau]

On X11, each widget has its own context. Make sure we are using the
widget associated context when using gl.

With gtk 3.16, glEGLImageTargetTexture2DOES() can be called during
update scanout, since we can call gtk_gl_area_make_current(). On < 3.16,
do it before drawing.

Fixes:
https://bugzilla.redhat.com/show_bug.cgi?id=1337721

Signed-off-by: Marc-André Lureau <marcandre.lureau at gmail.com>
---
 src/spice-widget-egl.c | 65 ++++++++++++++++++++++++++++++++++++++------------
 1 file changed, 50 insertions(+), 15 deletions(-)

diff --git a/src/spice-widget-egl.c b/src/spice-widget-egl.c
index 0054bc9..3ce574f 100644
--- a/src/spice-widget-egl.c
+++ b/src/spice-widget-egl.c
@@ -284,12 +284,38 @@ end:
     return TRUE;
 }
 
+static gboolean
+gl_make_current(SpiceDisplay *display, GError **err)
+{
+    SpiceDisplayPrivate *d = SPICE_DISPLAY_GET_PRIVATE(display);
+
+    if (GDK_IS_X11_DISPLAY(gdk_display_get_default())) {
+        EGLBoolean success = eglMakeCurrent(d->egl.display,
+                                            d->egl.surface,
+                                            d->egl.surface,
+                                            d->egl.ctx);
+        if (success != EGL_TRUE) {
+            g_set_error_literal(err, SPICE_CLIENT_ERROR,
+                                SPICE_CLIENT_ERROR_FAILED,
+                                "failed to activate context");
+            return FALSE;
+        }
+    } else {
+#if GTK_CHECK_VERSION(3,16,0)
+        GtkWidget *area = gtk_stack_get_child_by_name(d->stack, "gl-area");
+
+        gtk_gl_area_make_current(GTK_GL_AREA(area));
+#endif
+    }
+
+    return TRUE;
+}
+
 static gboolean spice_widget_init_egl_win(SpiceDisplay *display, GdkWindow *win,
                                           GError **err)
 {
     SpiceDisplayPrivate *d = SPICE_DISPLAY_GET_PRIVATE(display);
     EGLNativeWindowType native = 0;
-    EGLBoolean b;
 
     if (d->egl.surface)
         return TRUE;
@@ -316,15 +342,8 @@ static gboolean spice_widget_init_egl_win(SpiceDisplay *display, GdkWindow *win,
         return FALSE;
     }
 
-    b = eglMakeCurrent(d->egl.display,
-                       d->egl.surface,
-                       d->egl.surface,
-                       d->egl.ctx);
-    if (!b) {
-        g_set_error_literal(err, SPICE_CLIENT_ERROR, SPICE_CLIENT_ERROR_FAILED,
-                            "failed to activate context");
+    if (!gl_make_current(display, err))
         return FALSE;
-    }
 
     return TRUE;
 }
@@ -349,6 +368,9 @@ void spice_egl_unrealize_display(SpiceDisplay *display)
 
     SPICE_DEBUG("egl unrealize %p", d->egl.surface);
 
+    if (!gl_make_current(display, NULL))
+        return;
+
     if (d->egl.image != NULL) {
         eglDestroyImageKHR(d->egl.display, d->egl.image);
         d->egl.image = NULL;
@@ -402,6 +424,9 @@ void spice_egl_resize_display(SpiceDisplay *display, int w, int h)
     SpiceDisplayPrivate *d = SPICE_DISPLAY_GET_PRIVATE(display);
     int prog;
 
+    if (!gl_make_current(display, NULL))
+        return;
+
     glGetIntegerv(GL_CURRENT_PROGRAM, &prog);
 
     glUseProgram(d->egl.prog);
@@ -521,6 +546,8 @@ void spice_egl_update_display(SpiceDisplay *display)
     int prog;
 
     g_return_if_fail(d->ready);
+    if (!gl_make_current(display, NULL))
+        return;
 
     spice_display_get_scaling(display, &s, &x, &y, &w, &h);
 
@@ -553,8 +580,14 @@ void spice_egl_update_display(SpiceDisplay *display)
     }
     SPICE_DEBUG("update %f +%d+%d %dx%d +%f+%f %fx%f", s, x, y, w, h,
                 tx, ty, tw, th);
-
     glBindTexture(GL_TEXTURE_2D, d->egl.tex_id);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+
+#if !GTK_CHECK_VERSION(3,16,0)
+    glEGLImageTargetTexture2DOES(GL_TEXTURE_2D, (GLeglImageOES)d->egl.image);
+#endif
+
     glDisable(GL_BLEND);
     glGetIntegerv(GL_CURRENT_PROGRAM, &prog);
     glUseProgram(d->egl.prog);
@@ -588,7 +621,6 @@ void spice_egl_update_display(SpiceDisplay *display)
     glUseProgram(prog);
 }
 
-
 G_GNUC_INTERNAL
 gboolean spice_egl_update_scanout(SpiceDisplay *display,
                                   const SpiceGlScanout *scanout,
@@ -633,11 +665,14 @@ gboolean spice_egl_update_scanout(SpiceDisplay *display,
                                        (EGLClientBuffer)NULL,
                                        attrs);
 
-    glBindTexture(GL_TEXTURE_2D, d->egl.tex_id);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-    glEGLImageTargetTexture2DOES(GL_TEXTURE_2D, (GLeglImageOES)d->egl.image);
     d->egl.scanout = *scanout;
 
+#if GTK_CHECK_VERSION(3,16,0)
+    if (!gl_make_current(display, NULL))
+        return FALSE;
+
+    glEGLImageTargetTexture2DOES(GL_TEXTURE_2D, (GLeglImageOES)d->egl.image);
+#endif
+
     return TRUE;
 }
-- 
2.7.4