xephyr: Don't forget to glViewport() before drawing the screen.

Fixes misrendering with cairogears.  I had noticed the failure while
trying to figure out what was going on with traps.  Cairogears was
apparently putting its results on the screen through putimage, which
is a texture upload, so the last GL drawing was done to the size of
the cairogears window, not the size of the xephyr screen.

Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Keith Packard <keithp@keithp.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/hw/kdrive/ephyr/ephyr_glamor_glx.c b/hw/kdrive/ephyr/ephyr_glamor_glx.c
index d56907fe7..eaf565496 100644
--- a/hw/kdrive/ephyr/ephyr_glamor_glx.c
+++ b/hw/kdrive/ephyr/ephyr_glamor_glx.c
@@ -67,6 +67,9 @@ struct ephyr_glamor {
     GLuint texture_shader;
     GLuint texture_shader_position_loc;
     GLuint texture_shader_texcoord_loc;
+
+    /* Size of the window that we're rendering to. */
+    unsigned width, height;
 };
 
 static GLint
@@ -205,6 +208,7 @@ ephyr_glamor_damage_redisplay(struct ephyr_glamor *glamor,
 
     glBindFramebuffer(GL_FRAMEBUFFER, 0);
     glUseProgram(glamor->texture_shader);
+    glViewport(0, 0, glamor->width, glamor->height);
 
     glVertexAttribPointer(glamor->texture_shader_position_loc,
                           2, GL_FLOAT, FALSE, 0, position);
@@ -329,3 +333,14 @@ ephyr_glamor_get_visual(void)
 
     return xcb_aux_find_visual_by_id(xscreen, visual_info->visualid);
 }
+
+void
+ephyr_glamor_set_window_size(struct ephyr_glamor *glamor,
+                             unsigned width, unsigned height)
+{
+    if (!glamor)
+        return;
+
+    glamor->width = width;
+    glamor->height = height;
+}