// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef PPAPI_CPP_IMAGE_DATA_H_
#define PPAPI_CPP_IMAGE_DATA_H_
#include "ppapi/c/ppb_image_data.h"
#include "ppapi/cpp/point.h"
#include "ppapi/cpp/size.h"
#include "ppapi/cpp/resource.h"
/// @file
/// This file defines the APIs for determining how a browser
/// handles image data.
namespace pp {
class InstanceHandle;
class ImageData : public Resource {
public:
/// Default constructor for creating an is_null() <code>ImageData</code>
/// object.
ImageData();
/// A constructor used when you have received a <code>PP_Resource</code> as a
/// return value that has already been reference counted.
///
/// @param[in] resource A PP_Resource corresponding to image data.
ImageData(PassRef, PP_Resource resource);
/// The copy constructor for <code>ImageData</code>. This constructor
/// produces an <code>ImageData</code> object that shares the underlying
/// <code>Image</code> resource with <code>other</code>.
///
/// @param[in] other A pointer to an image data.
ImageData(const ImageData& other);
/// A constructor that allocates a new <code>ImageData</code> in the browser
/// with the provided parameters. The resulting object will be is_null() if
/// the allocation failed.
///
/// @param[in] instance The instance with which this resource will be
/// associated.
///
/// @param[in] format A PP_ImageDataFormat containing desired image format.
/// PP_ImageDataFormat is an enumeration of the different types of
/// image data formats. Refer to
/// <a href="../c/ppb__image__data_8h.html">
/// <code>ppb_image_data.h</code></a> for further information.
///
/// @param[in] size A pointer to a <code>Size</code> containing the image
/// size.
///
/// @param[in] init_to_zero A bool used to determine transparency at
/// creation. Set the <code>init_to_zero</code> flag if you want the bitmap
/// initialized to transparent during the creation process. If this flag is
/// not set, the current contents of the bitmap will be undefined, and the
/// module should be sure to set all the pixels.
ImageData(const InstanceHandle& instance,
PP_ImageDataFormat format,
const Size& size,
bool init_to_zero);
/// This function decrements the reference count of this
/// <code>ImageData</code> and increments the reference count of the
/// <code>other</code> <code>ImageData</code>. This <code>ImageData</code>
/// shares the underlying image resource with <code>other</code>.
///
/// @param[in] other An other image data.
///
/// @return A new image data context.
ImageData& operator=(const ImageData& other);
/// IsImageDataFormatSupported() returns <code>true</code> if the supplied
/// format is supported by the browser. Note:
/// <code>PP_IMAGEDATAFORMAT_BGRA_PREMUL</code> and
/// <code>PP_IMAGEDATAFORMAT_RGBA_PREMUL</code> formats are always supported.
/// Other image formats do not make this guarantee, and should be checked
/// first with IsImageDataFormatSupported() before using.
///
/// @param[in] format Image data format.
///
/// @return <code>true</code> if the format is supported by the browser.
static bool IsImageDataFormatSupported(PP_ImageDataFormat format);
/// GetNativeImageDataFormat() determines the browser's preferred format for
/// images. Using this format guarantees no extra conversions will occur when
/// painting.
///
/// @return <code>PP_ImageDataFormat</code> containing the preferred format.
static PP_ImageDataFormat GetNativeImageDataFormat();
/// A getter function for returning the current format for images.
///
/// @return <code>PP_ImageDataFormat</code> containing the preferred format.
PP_ImageDataFormat format() const { return desc_.format; }
/// A getter function for returning the image size.
///
/// @return The image size in pixels.
pp::Size size() const { return desc_.size; }
/// A getter function for returning the row width in bytes.
///
/// @return The row width in bytes.
int32_t stride() const { return desc_.stride; }
/// A getter function for returning a raw pointer to the image pixels.
///
/// @return A raw pointer to the image pixels.
void* data() const { return data_; }
/// This function is used retrieve the address of the given pixel for 32-bit
/// pixel formats.
///
/// @param[in] coord A <code>Point</code> representing the x and y
/// coordinates for a specific pixel.
///
/// @return The address for the pixel.
const uint32_t* GetAddr32(const Point& coord) const;
/// This function is used retrieve the address of the given pixel for 32-bit
/// pixel formats.
///
/// @param[in] coord A <code>Point</code> representing the x and y
/// coordinates for a specific pixel.
///
/// @return The address for the pixel.
uint32_t* GetAddr32(const Point& coord);
private:
void InitData();
PP_ImageDataDesc desc_;
void* data_;
};
} // namespace pp
#endif // PPAPI_CPP_IMAGE_DATA_H_