/*

* Copyright (c) 2003 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of the License "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description: Appearance interface

*

*/

#ifndef __M3G_APPEARANCE_H__

#define __M3G_APPEARANCE_H__

/*!

 * \internal

 * \file

 * \brief Appearance interface

 */

#include "m3g_object.h"

#include "m3g_compositingmode.h"

#include "m3g_polygonmode.h"

#include "m3g_material.h"

#include "m3g_texture.h"

#include "m3g_fog.h"

#include "m3g_rendercontext.h"

/* Limits for user settable layer */

#define M3G_APPEARANCE_MIN_LAYER      -63

#define M3G_APPEARANCE_MAX_LAYER       63

#define M3G_APPEARANCE_HARD_SORT_BITS   8

typedef /*@dependent@*//*@null@*/ Texture *TexturePtr;

/*!

 * \internal

 * \brief Appearance object

 */

struct M3GAppearanceImpl

{

    Object object;

    /*@dependent@*//*@null@*/

    Material *material;

    /*@dependent@*//*@null@*/

    CompositingMode *compositingMode;

    /*@dependent@*//*@null@*/

    PolygonMode *polygonMode;

    /*@dependent@*//*@null@*/

    Fog *fog;

    TexturePtr texture[M3G_NUM_TEXTURE_UNITS];

    M3Guint sortKey;

    M3Gshort layer;

    M3Gushort vertexMask;

};

/*----------------------------------------------------------------------

 * Internal functions

 *--------------------------------------------------------------------*/

static void m3gApplyAppearance(const Appearance *appearance,

							   RenderContext *ctx,

                               M3Gint alphaFactor);

/*!

 * \internal

 * \brief Get vertex mask

 *

 * \param app Appearance object

 * \return vertex mask

 */

static M3G_INLINE M3Gbitmask m3gGetVertexMask(const Appearance *app)

{

    return app->vertexMask;

}

/*!

 * \internal

 * \brief Shortcut getter for color mask

 */

static M3G_INLINE M3Gbool m3gColorMask(const Appearance *app)

{

    if (app) {

        const CompositingMode *cm = app->compositingMode;

        return !cm || cm->colorWrite;

    }

    return M3G_FALSE;

}

/*!

 * \internal

 * \brief Shortcut getter for alpha mask

 */

static M3G_INLINE M3Gbool m3gAlphaMask(const Appearance *app)

{

    if (app) {

        const CompositingMode *cm = app->compositingMode;

        return !cm || cm->alphaWrite;

    }

    return M3G_FALSE;

}

/*!

 * \internal

 * \brief Get sortkey for render queue

 *

 * Sort key is a combination of user settable layer and

 * blending mode. Blended objects are always drawn last.

 *

 * \param appearance    Appearance object

 * \return              sort key

 */

static M3G_INLINE M3Guint m3gGetAppearanceSortKey(const Appearance *appearance)

{

    if (appearance) {

        M3Guint key = appearance->sortKey;

        /* The blending state bit is set dynamically, as it may change

         * without changing the appearance (we have no signaling from

         * CompositingMode for that) */

        if (appearance->compositingMode != NULL

            && appearance->compositingMode->blendingMode != M3G_REPLACE) {

            key |= (1u << (32 - M3G_APPEARANCE_HARD_SORT_BITS));

        }

        if (m3gGetColorMaskWorkaround(M3G_INTERFACE(appearance))) {

            /* Override the top 2 bits of the sorting key so that ColorMask

             * changes are minimized */

            if (appearance) {

                key &= ~(0x03 << 22);

                key |= (((M3Guint) m3gColorMask(appearance)) & 1) << 23;

                key |= (((M3Guint) m3gAlphaMask(appearance)) & 1) << 22;

            }

        }

        return key;

    } 

    return M3G_FALSE;

}

/*!

 * \internal

 * \brief Release the textures bound for this appearance

 */

static void m3gReleaseTextures(const Appearance *appearance);

#endif /*__M3G_APPEARANCE_H__*/