[gimp/gimp-2-10] app: avoid starting the chunk renderer while finishing drawing a projection

[Ell <ell src gnome org>]

commit 18815512f2b1e45c43201c5b5c8178100a558d7e
Author: Ell <ell_se yahoo com>
Date:   Wed Nov 28 12:59:10 2018 -0500

    app: avoid starting the chunk renderer while finishing drawing a projection
    
    In gimp_projection_finish_draw(), make sure we don't accidentally
    re-start the chunk renderer idle source while running the remaining
    iterations, in case the chunk height changes, and we need to reinit
    the renderer state.
    
    (cherry picked from commit 8a47b6819439d16c140c40fbb14f95ad6ede0d3a)

 app/core/gimpprojection.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)
---
diff --git a/app/core/gimpprojection.c b/app/core/gimpprojection.c
index b416846809..f6d572b6a5 100644
--- a/app/core/gimpprojection.c
+++ b/app/core/gimpprojection.c
@@ -184,7 +184,8 @@ static void        gimp_projection_chunk_render_start    (GimpProjection  *proj)
 static void        gimp_projection_chunk_render_stop     (GimpProjection  *proj);
 static gboolean    gimp_projection_chunk_render_callback (gpointer         data);
 static void        gimp_projection_chunk_render_init     (GimpProjection  *proj);
-static void        gimp_projection_chunk_render_reinit   (GimpProjection  *proj);
+static void        gimp_projection_chunk_render_reinit   (GimpProjection  *proj,
+                                                          gboolean         assume_running);
 static gboolean    gimp_projection_chunk_render_iteration(GimpProjection  *proj,
                                                           gboolean         chunk);
 static gboolean    gimp_projection_chunk_render_next_area(GimpProjection  *proj);
@@ -603,7 +604,7 @@ gimp_projection_set_priority_rect (GimpProjection *proj,
       proj->priv->priority_rect = rect;
 
       if (proj->priv->chunk_render.idle_id)
-        gimp_projection_chunk_render_reinit (proj);
+        gimp_projection_chunk_render_reinit (proj, FALSE);
     }
 }
 
@@ -898,11 +899,12 @@ gimp_projection_chunk_render_init (GimpProjection *proj)
   chunk_render->target_n_pixels = GIMP_PROJECTION_CHUNK_WIDTH *
                                   GIMP_PROJECTION_CHUNK_HEIGHT;
 
-  gimp_projection_chunk_render_reinit (proj);
+  gimp_projection_chunk_render_reinit (proj, FALSE);
 }
 
 static void
-gimp_projection_chunk_render_reinit (GimpProjection *proj)
+gimp_projection_chunk_render_reinit (GimpProjection *proj,
+                                     gboolean        assume_running)
 {
   GimpProjectionChunkRender *chunk_render = &proj->priv->chunk_render;
 
@@ -928,7 +930,7 @@ gimp_projection_chunk_render_reinit (GimpProjection *proj)
    * its unrendered area with the update_areas list, and make it start
    * work on the next unrendered area in the list.
    */
-  if (chunk_render->idle_id)
+  if (chunk_render->idle_id || assume_running)
     {
       cairo_rectangle_int_t rect;
       gint                  work_h = 0;
@@ -1036,7 +1038,7 @@ gimp_projection_chunk_render_iteration (GimpProjection *proj,
        * current area, so that we're back at the beginning of a row
        */
       if (work_x != chunk_render->x)
-        gimp_projection_chunk_render_reinit (proj);
+        gimp_projection_chunk_render_reinit (proj, TRUE);
 
       chunk_render->work_height = work_h;
     }