/* 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.
*/
/**
* This file defines the <code>PPB_BrowserFont_Trusted</code> interface.
*/
label Chrome {
M19 = 1.0
};
[assert_size(4)]
enum PP_BrowserFont_Trusted_Family {
/**
* Uses the user's default web page font (normally either the default serif
* or sans serif font).
*/
PP_BROWSERFONT_TRUSTED_FAMILY_DEFAULT = 0,
/**
* These families will use the default web page font corresponding to the
* given family.
*/
PP_BROWSERFONT_TRUSTED_FAMILY_SERIF = 1,
PP_BROWSERFONT_TRUSTED_FAMILY_SANSSERIF = 2,
PP_BROWSERFONT_TRUSTED_FAMILY_MONOSPACE = 3
};
/**
* Specifies the font weight. Normally users will only use NORMAL or BOLD.
*/
[assert_size(4)]
enum PP_BrowserFont_Trusted_Weight {
PP_BROWSERFONT_TRUSTED_WEIGHT_100 = 0,
PP_BROWSERFONT_TRUSTED_WEIGHT_200 = 1,
PP_BROWSERFONT_TRUSTED_WEIGHT_300 = 2,
PP_BROWSERFONT_TRUSTED_WEIGHT_400 = 3,
PP_BROWSERFONT_TRUSTED_WEIGHT_500 = 4,
PP_BROWSERFONT_TRUSTED_WEIGHT_600 = 5,
PP_BROWSERFONT_TRUSTED_WEIGHT_700 = 6,
PP_BROWSERFONT_TRUSTED_WEIGHT_800 = 7,
PP_BROWSERFONT_TRUSTED_WEIGHT_900 = 8,
PP_BROWSERFONT_TRUSTED_WEIGHT_NORMAL =
PP_BROWSERFONT_TRUSTED_WEIGHT_400,
PP_BROWSERFONT_TRUSTED_WEIGHT_BOLD =
PP_BROWSERFONT_TRUSTED_WEIGHT_700
};
[assert_size(48)]
struct PP_BrowserFont_Trusted_Description {
/**
* Font face name as a string. This can also be an undefined var, in which
* case the generic family will be obeyed. If the face is not available on
* the system, the browser will attempt to do font fallback or pick a default
* font.
*/
PP_Var face;
/**
* When Create()ing a font and the face is an undefined var, the family
* specifies the generic font family type to use. If the face is specified,
* this will be ignored.
*
* When Describe()ing a font, the family will be the value you passed in when
* the font was created. In other words, if you specify a face name, the
* family will not be updated to reflect whether the font name you requested
* is serif or sans serif.
*/
PP_BrowserFont_Trusted_Family family;
/**
* Size in pixels.
*
* You can specify 0 to get the default font size. The default font size
* may vary depending on the requested font. The typical example is that
* the user may have a different font size for the default monospace font to
* give it a similar optical size to the proportionally spaced fonts.
*/
uint32_t size;
/**
* Normally you will use either normal or bold.
*/
PP_BrowserFont_Trusted_Weight weight;
PP_Bool italic;
PP_Bool small_caps;
/**
* Adjustment to apply to letter and word spacing, respectively. Initialize
* to 0 to get normal spacing. Negative values bring letters/words closer
* together, positive values separate them.
*/
int32_t letter_spacing;
int32_t word_spacing;
/**
* Ensure that this struct is 48-bytes wide by padding the end. In some
* compilers, PP_Var is 8-byte aligned, so those compilers align this struct
* on 8-byte boundaries as well and pad it to 16 bytes even without this
* padding attribute. This padding makes its size consistent across
* compilers.
*/
int32_t padding;
};
[assert_size(20)]
struct PP_BrowserFont_Trusted_Metrics {
int32_t height;
int32_t ascent;
int32_t descent;
int32_t line_spacing;
int32_t x_height;
};
[assert_size(24)]
struct PP_BrowserFont_Trusted_TextRun {
/**
* This var must either be a string or a null/undefined var (which will be
* treated as a 0-length string).
*/
PP_Var text;
/**
* Set to PP_TRUE if the text is right-to-left.
*/
PP_Bool rtl;
/**
* Set to PP_TRUE to force the directionality of the text regardless of
* content
*/
PP_Bool override_direction;
};
/**
* Provides an interface for native browser text rendering.
*
* This API is "trusted" not for security reasons, but because it can not be
* implemented efficiently when running out-of-process in Browser Client. In
* this case, WebKit is in another process and every text call would require a
* synchronous IPC to the renderer. It is, however, available to native
* (non-NaCl) out-of-process PPAPI plugins since WebKit is available in the
* plugin process.
*/
interface PPB_BrowserFont_Trusted {
/**
* Returns a list of all available font families on the system. You can use
* this list to decide whether to Create() a font.
*
* The return value will be a single string with null characters delimiting
* the end of each font name. For example: "Arial\0Courier\0Times\0".
*
* Returns an undefined var on failure (this typically means you passed an
* invalid instance).
*/
PP_Var GetFontFamilies(
[in] PP_Instance instance);
/**
* Returns a font which best matches the given description. The return value
* will have a non-zero ID on success, or zero on failure.
*/
PP_Resource Create(
[in] PP_Instance instance,
[in] PP_BrowserFont_Trusted_Description description);
/**
* Returns PP_TRUE if the given resource is a Font. Returns PP_FALSE if the
* resource is invalid or some type other than a Font.
*/
PP_Bool IsFont(
[in] PP_Resource resource);
/**
* Loads the description and metrics of the font into the given structures.
* The description will be different than the description the font was
* created with since it will be filled with the real values from the font
* that was actually selected.
*
* The PP_Var in the description should be of type Void on input. On output,
* this will contain the string and will have a reference count of 1. The
* plugin is responsible for calling Release on this var.
*
* Returns PP_TRUE on success, PP_FALSE if the font is invalid or if the Var
* in the description isn't Null (to prevent leaks).
*/
PP_Bool Describe(
[in] PP_Resource font,
[out] PP_BrowserFont_Trusted_Description description,
[out] PP_BrowserFont_Trusted_Metrics metrics);
/**
* Draws the text to the image buffer.
*
* The given point represents the baseline of the left edge of the font,
* regardless of whether it is left-to-right or right-to-left (in the case of
* RTL text, this will actually represent the logical end of the text).
*
* The clip is optional and may be NULL. In this case, the text will be
* clipped to the image.
*
* The image_data_is_opaque flag indicates whether subpixel antialiasing can
* be performed, if it is supported. When the image below the text is
* opaque, subpixel antialiasing is supported and you should set this to
* PP_TRUE to pick up the user's default preferences. If your plugin is
* partially transparent, then subpixel antialiasing is not possible and
* grayscale antialiasing will be used instead (assuming the user has
* antialiasing enabled at all).
*/
PP_Bool DrawTextAt(
[in] PP_Resource font,
[in] PP_Resource image_data,
[in] PP_BrowserFont_Trusted_TextRun text,
[in] PP_Point position,
[in] uint32_t color,
[in] PP_Rect clip,
[in] PP_Bool image_data_is_opaque);
/**
* Returns the width of the given string. If the font is invalid or the var
* isn't a valid string, this will return -1.
*
* Note that this function handles complex scripts such as Arabic, combining
* accents, etc. so that adding the width of substrings won't necessarily
* produce the correct width of the entire string.
*
* Returns -1 on failure.
*/
int32_t MeasureText(
[in] PP_Resource font,
[in] PP_BrowserFont_Trusted_TextRun text);
/**
* Returns the character at the given pixel X position from the beginning of
* the string. This handles complex scripts such as Arabic, where characters
* may be combined or replaced depending on the context. Returns (uint32)-1
* on failure.
*
* TODO(brettw) this function may be broken. See the CharPosRTL test. It
* seems to tell you "insertion point" rather than painting position. This
* is useful but maybe not what we intended here.
*/
uint32_t CharacterOffsetForPixel(
[in] PP_Resource font,
[in] PP_BrowserFont_Trusted_TextRun text,
[in] int32_t pixel_position);
/**
* Returns the horizontal advance to the given character if the string was
* placed at the given position. This handles complex scripts such as Arabic,
* where characters may be combined or replaced depending on context. Returns
* -1 on error.
*/
int32_t PixelOffsetForCharacter(
[in] PP_Resource font,
[in] PP_BrowserFont_Trusted_TextRun text,
[in] uint32_t char_offset);
};
