st/mesa: add support for GL_ARB_viewport_array (v0.2)

this just ties the mesa code to the pre-existing gallium interface,
I'm not sure what to do with the CSO stuff yet.

0.2: fix min/max bounds

Acked-by: Ilia Mirkin <[email protected]>
Signed-off-by: Dave Airlie <[email protected]>

1 files changed, 9 insertions, 0 deletions

diff --git a/src/mesa/state_tracker/st_extensions.c b/src/mesa/state_tracker/st_extensions.c
index f9b7a445f1f..1f391c9f0dd 100644
--- a/src/mesa/state_tracker/st_extensions.c
+++ b/src/mesa/state_tracker/st_extensions.c
@@ -779,4 +779,13 @@ void st_init_extensions(struct st_context *st)
       if (!ctx->Extensions.EXT_transform_feedback)
          ctx->Const.DisableVaryingPacking = GL_TRUE;
    }
+
+   if (ctx->API == API_OPENGL_CORE) {
+      ctx->Const.MaxViewports = screen->get_param(screen, PIPE_CAP_MAX_VIEWPORTS);
+      if (ctx->Const.MaxViewports >= 16) {
+         ctx->Const.ViewportBounds.Min = -(float)ctx->Const.MaxViewportWidth;
+         ctx->Const.ViewportBounds.Max = ctx->Const.MaxViewportWidth;
+         ctx->Extensions.ARB_viewport_array = GL_TRUE;
+      }
+   }
 }