Mesa (master): st/mesa: allow glDrawElements to work with GL_SELECT feedback

[GitLab Mirror]

Module: Mesa
Branch: master
Commit: bac85342672a265735316049ecf36b74e1f2a852
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=bac85342672a265735316049ecf36b74e1f2a852

Author: Ilia Mirkin <imirkin at alum.mit.edu>
Date:   Tue Dec 18 22:47:05 2018 -0500

st/mesa: allow glDrawElements to work with GL_SELECT feedback

Not sure if this ever worked, but the current logic for setting the
min/max index is definitely wrong for indexed draws. While we're at it,
bring in all the usual logic from the non-indirect drawing path.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=109086
Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
Reviewed-by: Brian Paul <brianp at vmware.com>
Reviewed-by: Roland Scheidegger <sroland at vmware.com>

---

 src/mesa/state_tracker/st_draw.c          |  2 +
 src/mesa/state_tracker/st_draw_feedback.c | 63 ++++++++++++++++++++-----------
 2 files changed, 42 insertions(+), 23 deletions(-)

diff --git a/src/mesa/state_tracker/st_draw.c b/src/mesa/state_tracker/st_draw.c
index 9600b1569d..0a190bd8ba 100644
--- a/src/mesa/state_tracker/st_draw.c
+++ b/src/mesa/state_tracker/st_draw.c
@@ -160,6 +160,8 @@ prepare_draw(struct st_context *st, struct gl_context *ctx)
  * This function gets plugged into the VBO module and is called when
  * we have something to render.
  * Basically, translate the information into the format expected by gallium.
+ *
+ * Try to keep this logic in sync with st_feedback_draw_vbo.
  */
 static void
 st_draw_vbo(struct gl_context *ctx,
diff --git a/src/mesa/state_tracker/st_draw_feedback.c b/src/mesa/state_tracker/st_draw_feedback.c
index 6ec6d5c16f..b83f63811d 100644
--- a/src/mesa/state_tracker/st_draw_feedback.c
+++ b/src/mesa/state_tracker/st_draw_feedback.c
@@ -85,30 +85,9 @@ set_feedback_vertex_format(struct gl_context *ctx)
 
 
 /**
- * Helper for drawing current vertex arrays.
- */
-static void
-draw_arrays(struct draw_context *draw, unsigned mode,
-            unsigned start, unsigned count)
-{
-   struct pipe_draw_info info;
-
-   util_draw_init_info(&info);
-
-   info.mode = mode;
-   info.start = start;
-   info.count = count;
-   info.min_index = start;
-   info.max_index = start + count - 1;
-
-   draw_vbo(draw, &info);
-}
-
-
-/**
  * Called by VBO to draw arrays when in selection or feedback mode and
  * to implement glRasterPos.
- * This is very much like the normal draw_vbo() function above.
+ * This function mirrors the normal st_draw_vbo().
  * Look at code refactoring some day.
  */
 void
@@ -136,10 +115,18 @@ st_feedback_draw_vbo(struct gl_context *ctx,
    struct pipe_transfer *ib_transfer = NULL;
    GLuint i;
    const void *mapped_indices = NULL;
+   struct pipe_draw_info info;
 
    if (!draw)
       return;
 
+   /* Initialize pipe_draw_info. */
+   info.primitive_restart = false;
+   info.vertices_per_patch = ctx->TessCtrlProgram.patch_vertices;
+   info.indirect = NULL;
+   info.count_from_stream_output = NULL;
+   info.restart_index = 0;
+
    st_flush_bitmap_cache(st);
    st_invalidate_readpix_cache(st);
 
@@ -213,9 +200,23 @@ st_feedback_draw_vbo(struct gl_context *ctx,
          mapped_indices = ib->ptr;
       }
 
+      info.index_size = ib->index_size;
+      info.min_index = min_index;
+      info.max_index = max_index;
+      info.has_user_indices = true;
+      info.index.user = mapped_indices;
+
       draw_set_indexes(draw,
                        (ubyte *) mapped_indices,
                        index_size, ~0);
+
+      if (ctx->Array._PrimitiveRestart) {
+         info.primitive_restart = true;
+         info.restart_index = _mesa_primitive_restart_index(ctx, info.index_size);
+      }
+   } else {
+      info.index_size = 0;
+      info.has_user_indices = false;
    }
 
    /* set the constant buffer */
@@ -226,7 +227,23 @@ st_feedback_draw_vbo(struct gl_context *ctx,
 
    /* draw here */
    for (i = 0; i < nr_prims; i++) {
-      draw_arrays(draw, prims[i].mode, start + prims[i].start, prims[i].count);
+      info.count = prims[i].count;
+
+      if (!info.count)
+         continue;
+
+      info.mode = prims[i].mode;
+      info.start = start + prims[i].start;
+      info.start_instance = prims[i].base_instance;
+      info.instance_count = prims[i].num_instances;
+      info.index_bias = prims[i].basevertex;
+      info.drawid = prims[i].draw_id;
+      if (!ib) {
+         info.min_index = info.start;
+         info.max_index = info.start + info.count - 1;
+      }
+
+      draw_vbo(draw, &info);
    }