/*

* Copyright (c) 2006-2007 Nokia Corporation and/or its subsidiary(-ies). 

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "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:   Declares the MHuiTexture interface. MHuiTexture is the most 

*                generic interface that all textures need to implement.

*

*/

#ifndef __HUITEXTUREIF_H__

#define __HUITEXTUREIF_H__

/* Forward declarations. */

class MHuiSegmentedTexture;

class MHuiShadowedTexture;

/** Data buffer formats for uploading textures. */

enum THuiTextureFormat

    {

    /** RGB, 5-6-5 bits per channel. */

    EHuiTextureFormatRgb565,

    /** RGB, 8 bits per channel. */

    EHuiTextureFormatRgb888,

    /** RGBA, 8 bits per channel. */

    EHuiTextureFormatRgba8888,

    /** Luminance + Alpha, 8 bits per channel. */

    EHuiTextureFormatLa88,

    /** RGB, PVRTC 4 bpp. */

    EHuiTextureFormatRgbPVRTC4,

    /** RGBA, PVRTC 4 bpp. */

    EHuiTextureFormatRgbaPVRTC4,

    /** RGB, PVRTC 2 bpp. */

    EHuiTextureFormatRgbPVRTC2,

    /** RGBA, PVRTC 2 bpp. */

    EHuiTextureFormatRgbaPVRTC2

    };

/** Flags for texture uploading. */

enum THuiTextureUploadFlags

    {

    /** No special actions/behavior needed. */

    EHuiTextureUploadFlagDefault = 0,

    /**

     * @deprecated This is default functionality 

     */

    EHuiTextureUploadFlagRetainResolution = 1,

    /**

     * Automatically generates a shadow for the texture in texture upload

     * phase.

     */

    EHuiTextureUploadFlagGenerateShadow = 2,

    /**

     * Use to retain the color depth of the

     * ((up)loaded) image as well as possible. Otherwise

     * the toolkit may reduce the color depth of the texture

     * to conserve memory.

     */

    EHuiTextureUploadFlagRetainColorDepth = 4,

    // note: value 0x8 is reserved in client server model so we leave hole here

    /**

     * Set if it is not necessary to retain the

     * full resolution of the bitmap (tries to match texture resolution

     * with bitmap resolution).

     * This may save some memory with hardware acceleration, but image quality changes to worse

     */

    EHuiTextureUploadFlagDoNotRetainResolution = 0x10,

    /**

     * Use the provided bitmap directly for the texture, without conversion or copying. The bitmaps

     * should be in the correct format and they shall not be compressed or have duplicated handle.

     * If the direct bitmap cannot be used, this flag is ignored internally.

     */

    EHuiTextureFlagAllowDirectBitmapUsage = 0x20,

    /**

     * If given to texture's SegmentUpload() while bitmap being uploaded is in NVG format,

     * the texture will have NVG ObjectCached data created for quicker drawing. 

     * 

     * By default if no flags is given as parameters, the NVG data will be rasterized

     * into PBuffer (=VGImage) during upload, since using VGImages is the fastet way.

     */

    EHuiTextureUploadFlagUsePureNvg = 0x40

    };

/**

 * MHuiTexture is the most generic interface that all texture classes need to

 * implement. Using MHuiTexture, it is possible to determine which interfaces

 * a specific texture supports.

 */

class MHuiTexture

    {

public:

    /* Destructor. */

    /**

     * Virtual destructor.

     */

    IMPORT_C virtual ~MHuiTexture();

    /* Interface methods. */

    /**

     * @return  The texture as a MHuiSegmentedTexture interface, or NULL is

     *          the texture does not implement the segmented texture interface.

     */

    virtual MHuiSegmentedTexture* SegmentedTexture() = 0;

    virtual const MHuiSegmentedTexture* SegmentedTexture() const = 0;

    /**

     * @return  The texture as a MHuiShadowedTexture interface, or NULL is

     *          the texture does not implement the shadowed texture interface.

     */

    virtual MHuiShadowedTexture* ShadowedTexture() = 0;

    virtual const MHuiShadowedTexture* ShadowedTexture() const = 0;

    /**

     * Returns true if the texture has changed since the last change

     * notification. Changed means that the bitmap data of the texture

     * has been modified, and must be re-uploaded to texture memory.

     */

	virtual TBool TextureChanged() const = 0;

    /**

     * Clears the changed status of the visual.

     */

	virtual void TextureClearChanged() const = 0;    

    /**

     * Determines whether the texture has content. Only textures that

     * have content can be drawn.

     *

     * Note that a texture that has not finished loading will return EFalse

     * here, because its content will only become available after it has

     * been fully loaded.

     *

     * @return ETrue, if this texture has content.

     */

    virtual TBool HasContent() const = 0;

    virtual void TextureExtension(const TUid& aExtensionUid, TAny** aExtensionParameters) = 0; 

    };

#endif // __HUITEXTUREIF_H__