src/gallium/drivers/svga/svga_sampler_view.h

/**********************************************************
 * Copyright 2008-2009 VMware, Inc.  All rights reserved.
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
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 * of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
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 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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#ifndef SVGA_SAMPLER_VIEW_H
#define SVGA_SAMPLER_VIEW_H


#include "pipe/p_compiler.h"
#include "pipe/p_state.h"
#include "util/u_inlines.h"
#include "svga_screen_cache.h"

struct pipe_context;
struct pipe_screen;
struct svga_context;
struct svga_winsys_surface;
enum SVGA3dSurfaceFormat;


/**
 * A sampler's view into a texture
 *
 * We currently cache one sampler view on
 * the texture and in there by holding a reference
 * from the texture to the sampler view.
 *
 * Because of this we can not hold a refernce to the
 * texture from the sampler view. So the user
 * of the sampler views must make sure that the
 * texture has a reference take for as long as
 * the sampler view is refrenced.
 *
 * Just unreferencing the sampler_view before the
 * texture is enough.
 */
struct svga_sampler_view
{
   struct pipe_reference reference;

   struct pipe_resource *texture;

   int min_lod;
   int max_lod;

   unsigned age;

   struct svga_host_surface_cache_key key;
   struct svga_winsys_surface *handle;
};



extern struct svga_sampler_view *
svga_get_tex_sampler_view(struct pipe_context *pipe,
                          struct pipe_resource *pt,
                          unsigned min_lod, unsigned max_lod);

void
svga_validate_sampler_view(struct svga_context *svga, struct svga_sampler_view *v);

void
svga_destroy_sampler_view_priv(struct svga_sampler_view *v);

void
svga_debug_describe_sampler_view(char *buf, const struct svga_sampler_view *sv);

static INLINE void
svga_sampler_view_reference(struct svga_sampler_view **ptr, struct svga_sampler_view *v)
{
   struct svga_sampler_view *old = *ptr;

   if (pipe_reference_described(&(*ptr)->reference, &v->reference, 
                                (debug_reference_descriptor)svga_debug_describe_sampler_view))
      svga_destroy_sampler_view_priv(old);
   *ptr = v;
}


#endif