chromium/ppapi/c/ppb_image_data.h

/* Copyright 2012 The Chromium Authors
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

/* From ppb_image_data.idl modified Tue Nov 13 08:48:25 2012. */

#ifndef PPAPI_C_PPB_IMAGE_DATA_H_
#define PPAPI_C_PPB_IMAGE_DATA_H_

#include "ppapi/c/pp_bool.h"
#include "ppapi/c/pp_instance.h"
#include "ppapi/c/pp_macros.h"
#include "ppapi/c/pp_resource.h"
#include "ppapi/c/pp_size.h"
#include "ppapi/c/pp_stdint.h"

#define PPB_IMAGEDATA_INTERFACE_1_0 …
#define PPB_IMAGEDATA_INTERFACE …

/**
 * @file
 * This file defines the <code>PPB_ImageData</code> struct for determining how
 * a browser handles image data.
 */


/**
 * @addtogroup Enums
 * @{
 */
/**
 * <code>PP_ImageDataFormat</code> is an enumeration of the different types of
 * image data formats.
 *
 * The third part of each enumeration value describes the memory layout from
 * the lowest address to the highest. For example, BGRA means the B component
 * is stored in the lowest address, no matter what endianness the platform is
 * using.
 *
 * The PREMUL suffix implies pre-multiplied alpha is used. In this mode, the
 * red, green and blue color components of the pixel data supplied to an image
 * data should be pre-multiplied by their alpha value. For example: starting
 * with floating point color components, here is how to convert them to 8-bit
 * premultiplied components for image data:
 *
 * ...components of a pixel, floats ranging from 0 to 1...
 * <code>float red = 1.0f;</code>
 * <code>float green = 0.50f;</code>
 * <code>float blue = 0.0f;</code>
 * <code>float alpha = 0.75f;</code>
 * ...components for image data are 8-bit values ranging from 0 to 255...
 * <code>uint8_t image_data_red_premul = (uint8_t)(red * alpha * 255.0f);
 * </code>
 * <code>uint8_t image_data_green_premul = (uint8_t)(green * alpha * 255.0f);
 * </code>
 * <code>uint8_t image_data_blue_premul = (uint8_t)(blue * alpha * 255.0f);
 * </code>
 * <code>uint8_t image_data_alpha_premul = (uint8_t)(alpha * 255.0f);</code>
 *
 * <strong>Note:</strong> The resulting pre-multiplied red, green and blue
 * components should not be greater than the alpha value.
 */
PP_ImageDataFormat;
PP_COMPILE_ASSERT_SIZE_IN_BYTES(…);
/**
 * @}
 */

/**
 * @addtogroup Structs
 * @{
 */
/**
 * The <code>PP_ImageDataDesc</code> structure represents a description of
 * image data.
 */
struct PP_ImageDataDesc { … };
PP_COMPILE_ASSERT_STRUCT_SIZE_IN_BYTES(…);
/**
 * @}
 */

/**
 * @addtogroup Interfaces
 * @{
 */
/**
 * The <code>PPB_ImageData</code> interface contains pointers to several
 * functions for determining the browser's treatment of image data.
 */
struct PPB_ImageData_1_0 { … };

PPB_ImageData;
/**
 * @}
 */

#endif  /* PPAPI_C_PPB_IMAGE_DATA_H_ */