st/mesa: fix GL_FEEDBACK mode inverted Y coordinate bug

We need to check the drawbuffer's orientation before inverting Y
coordinates.  Fixes piglit feedback tests when running with the
-fbo option.

Cc: "9.2" "10.0" <[email protected]>

Reviewed-by: Marek Olšák <[email protected]>
(cherry picked from commit 15d8e05e1e98a9bfd5a365d0fda222668f24261f)

1 files changed, 4 insertions, 2 deletions

diff --git a/src/mesa/state_tracker/st_cb_feedback.c b/src/mesa/state_tracker/st_cb_feedback.c
index d2e4346b7ea..34a16ccf938 100644
--- a/src/mesa/state_tracker/st_cb_feedback.c
+++ b/src/mesa/state_tracker/st_cb_feedback.c
@@ -85,9 +85,11 @@ feedback_vertex(struct gl_context *ctx, const struct draw_context *draw,
    const GLfloat *color, *texcoord;
    GLuint slot;
 
-   /* Recall that Y=0=Top of window for Gallium wincoords */
    win[0] = v->data[0][0];
-   win[1] = ctx->DrawBuffer->Height - v->data[0][1];
+   if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP)
+      win[1] = ctx->DrawBuffer->Height - v->data[0][1];
+   else
+      win[1] = v->data[0][1];
    win[2] = v->data[0][2];
    win[3] = 1.0F / v->data[0][3];