Auto merge of #269 - jrmuizel:run, r=jdm

Add some minimal bindings for CTLine and CTRun

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Author: bors-servo

core-text/src/lib.rs

@@ -25,3 +25,6 @@ pub mod font_descriptor;
 pub mod font_manager;
 pub mod frame;
 pub mod framesetter;
+pub mod line;
+pub mod run;
+pub mod string_attributes;

core-text/src/line.rs

@@ -0,0 +1,47 @@
+// Copyright 2013 The Servo Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use std::os::raw::c_void;
+use core_foundation::attributed_string::CFAttributedStringRef;
+use core_foundation::array::{CFArray, CFArrayRef};
+use core_foundation::base::{CFTypeID, TCFType};
+use run::CTRun;
+
+#[repr(C)]
+pub struct __CTLine(c_void);
+
+pub type CTLineRef = *const __CTLine;
+
+declare_TCFType! {
+    CTLine, CTLineRef
+}
+impl_TCFType!(CTLine, CTLineRef, CTLineGetTypeID);
+impl_CFTypeDescription!(CTLine);
+
+impl CTLine {
+    pub fn new_with_attributed_string(string: CFAttributedStringRef) -> Self {
+        unsafe {
+            let ptr = CTLineCreateWithAttributedString(string);
+            CTLine::wrap_under_create_rule(ptr)
+        }
+    }
+
+    pub fn glyph_runs(&self) -> CFArray<CTRun> {
+        unsafe {
+            TCFType::wrap_under_get_rule(CTLineGetGlyphRuns(self.0))
+        }
+    }
+}
+
+#[link(name = "CoreText", kind = "framework")]
+extern {
+    fn CTLineGetTypeID() -> CFTypeID;
+    fn CTLineGetGlyphRuns(line: CTLineRef) -> CFArrayRef;
+    fn CTLineCreateWithAttributedString(string: CFAttributedStringRef) -> CTLineRef;
+}

core-text/src/run.rs

@@ -0,0 +1,129 @@
+// Copyright 2013 The Servo Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use std::borrow::Cow;
+use std::os::raw::c_void;
+use std::slice;
+use std::ptr;
+use core_foundation::base::{CFIndex, CFTypeID, TCFType, CFType, CFRange};
+use core_foundation::dictionary::{CFDictionary, CFDictionaryRef};
+use core_foundation::string::CFString;
+use core_graphics::font::CGGlyph;
+use core_graphics::geometry::CGPoint;
+
+#[repr(C)]
+pub struct __CTRun(c_void);
+
+pub type CTRunRef = *const __CTRun;
+
+declare_TCFType! {
+    CTRun, CTRunRef
+}
+impl_TCFType!(CTRun, CTRunRef, CTRunGetTypeID);
+impl_CFTypeDescription!(CTRun);
+
+impl CTRun {
+    pub fn attributes(&self) -> Option<CFDictionary<CFString, CFType>> {
+        unsafe {
+            let attrs = CTRunGetAttributes(self.0);
+            if attrs.is_null() {
+                return None;
+            }
+            Some(TCFType::wrap_under_get_rule(attrs))
+        }
+    }
+    pub fn glyph_count(&self) -> CFIndex {
+        unsafe {
+            CTRunGetGlyphCount(self.0)
+        }
+    }
+
+    pub fn glyphs(&self) -> Cow<[CGGlyph]> {
+        unsafe {
+            // CTRunGetGlyphsPtr can return null under some not understood circumstances.
+            // If it does the Apple documentation tells us to allocate our own buffer and call
+            // CTRunGetGlyphs
+            let count = CTRunGetGlyphCount(self.0);
+            let glyphs_ptr = CTRunGetGlyphsPtr(self.0);
+            if glyphs_ptr != ptr::null() {
+                Cow::from(slice::from_raw_parts(glyphs_ptr, count as usize))
+            } else {
+                let mut vec = Vec::with_capacity(count as usize);
+                // "If the length of the range is set to 0, then the copy operation will continue
+                // from the start index of the range to the end of the run"
+                CTRunGetGlyphs(self.0, CFRange::init(0, 0), vec.as_mut_ptr());
+                vec.set_len(count as usize);
+                Cow::from(vec)
+            }
+        }
+    }
+
+    pub fn positions(&self) -> Cow<[CGPoint]> {
+        unsafe {
+            // CTRunGetPositionsPtr can return null under some not understood circumstances.
+            // If it does the Apple documentation tells us to allocate our own buffer and call
+            // CTRunGetPositions
+            let count = CTRunGetGlyphCount(self.0);
+            let positions_ptr = CTRunGetPositionsPtr(self.0);
+            if positions_ptr != ptr::null() {
+                Cow::from(slice::from_raw_parts(positions_ptr, count as usize))
+            } else {
+                let mut vec = Vec::with_capacity(count as usize);
+                // "If the length of the range is set to 0, then the copy operation will continue
+                // from the start index of the range to the end of the run"
+                CTRunGetPositions(self.0, CFRange::init(0, 0), vec.as_mut_ptr());
+                vec.set_len(count as usize);
+                Cow::from(vec)
+            }
+        }
+    }
+
+}
+
+#[test]
+fn create_runs() {
+    use core_foundation::attributed_string::CFMutableAttributedString;
+    use string_attributes::*;
+    use line::*;
+    use font;
+    let mut string = CFMutableAttributedString::new();
+    string.replace_str(&CFString::new("Food"), CFRange::init(0, 0));
+    let len = string.char_len();
+    unsafe {
+        string.set_attribute(CFRange::init(0, len), kCTFontAttributeName, font::new_from_name("Helvetica", 16.).unwrap());
+    }
+    let line = CTLine::new_with_attributed_string(string.as_concrete_TypeRef());
+    let runs = line.glyph_runs();
+    assert_eq!(runs.len(), 1);
+    for run in runs.iter() {
+        assert_eq!(run.glyph_count(), 4);
+        let font = run.attributes().unwrap().get(CFString::new("NSFont")).downcast::<font::CTFont>().unwrap();
+        assert_eq!(font.pt_size(), 16.);
+
+        let positions = run.positions();
+        assert_eq!(positions.len(), 4);
+        assert!(positions[0].x < positions[1].x);
+
+        let glyphs = run.glyphs();
+        assert_eq!(glyphs.len(), 4);
+        assert_ne!(glyphs[0], glyphs[1]);
+        assert_eq!(glyphs[1], glyphs[2]);
+    }
+}
+
+#[link(name = "CoreText", kind = "framework")]
+extern {
+    fn CTRunGetTypeID() -> CFTypeID;
+    fn CTRunGetAttributes(run: CTRunRef) -> CFDictionaryRef;
+    fn CTRunGetGlyphCount(run: CTRunRef) -> CFIndex;
+    fn CTRunGetPositionsPtr(run: CTRunRef) -> *const CGPoint;
+    fn CTRunGetPositions(run: CTRunRef, range: CFRange, buffer: *const CGPoint);
+    fn CTRunGetGlyphsPtr(run: CTRunRef) -> *const CGGlyph;
+    fn CTRunGetGlyphs(run: CTRunRef, range: CFRange, buffer: *const CGGlyph);
+}

core-text/src/string_attributes.rs

@@ -0,0 +1,19 @@
+use core_foundation::string::CFStringRef;
+
+extern {
+    pub static kCTCharacterShapeAttributeName: CFStringRef;
+    pub static kCTFontAttributeName: CFStringRef;
+    pub static kCTKernAttributeName: CFStringRef;
+    pub static kCTLigatureAttributeName: CFStringRef;
+    pub static kCTForegroundColorAttributeName: CFStringRef;
+    pub static kCTForegroundColorFromContextAttributeName: CFStringRef;
+    pub static kCTParagraphStyleAttributeName: CFStringRef;
+    pub static kCTStrokeWidthAttributeName: CFStringRef;
+    pub static kCTStrokeColorAttributeName: CFStringRef;
+    pub static kCTSuperscriptAttributeName: CFStringRef;
+    pub static kCTUnderlineColorAttributeName: CFStringRef;
+    pub static kCTUnderlineStyleAttributeName: CFStringRef;
+    pub static kCTVerticalFormsAttributeName: CFStringRef;
+    pub static kCTGlyphInfoAttributeName: CFStringRef;
+    pub static kCTRunDelegateAttributeName: CFStringRef;
+}