Fix the linux build by stubbing out FreeType handles that haven't bee…

…n implemented yet. Add some glue to create ScaledFonts for Cairo backend on linux. Closes #207.

src/servo-gfx/font.rs

@@ -7,6 +7,7 @@ use text::glyph::{GlyphStore, GlyphIndex};
 use text::{Shaper, TextRun};
 
 use azure::{AzFloat, AzScaledFontRef};
+use azure::scaled_font::ScaledFont;
 use azure::azure_hl::{BackendType, ColorPattern};
 use core::dvec::DVec;
 use geom::{Point2D, Rect, Size2D};
@@ -44,13 +45,13 @@ pub trait FontHandleMethods {
 
 impl FontHandle {
     #[cfg(target_os = "macos")]
-    static pub fn new(fctx: &native::FontContextHandle, buf: ~[u8], style: &SpecifiedFontStyle) -> Result<FontHandle, ()> {
+    static pub fn new_from_buffer(fctx: &native::FontContextHandle, buf: ~[u8], style: &SpecifiedFontStyle) -> Result<FontHandle, ()> {
         quartz::font::QuartzFontHandle::new_from_buffer(fctx, move buf, style)
     }
 
     #[cfg(target_os = "linux")]
-    static pub fn new(fctx: &native::FontContextHandle, buf: ~[u8], style: &SpecifiedFontStyle) -> Result<FontHandle, ()> {
-        freetype::font::FreeTypeFontHandle::new(fctx, move buf, style)
+    static pub fn new_from_buffer(fctx: &native::FontContextHandle, buf: ~[u8], style: &SpecifiedFontStyle) -> Result<FontHandle, ()> {
+        freetype::font::FreeTypeFontHandle::new_from_buffer(fctx, move buf, style)
     }
 }
 
@@ -241,23 +242,18 @@ and the renderer can use it to render text.
 */
 pub struct Font {
     priv handle: FontHandle,
-    priv mut azure_font: Option<AzScaledFontRef>,
+    priv mut azure_font: Option<ScaledFont>,
     priv mut shaper: Option<@Shaper>,
     style: UsedFontStyle,
     metrics: FontMetrics,
     backend: BackendType,
-
-    drop {
-        use azure::bindgen::AzReleaseScaledFont;
-        do (copy self.azure_font).iter |fontref| { AzReleaseScaledFont(*fontref); }
-    }
 }
 
 impl Font {
     static fn new_from_buffer(ctx: &FontContext, buffer: ~[u8],
                               style: &SpecifiedFontStyle, backend: BackendType) -> Result<@Font, ()> {
 
-        let handle = FontHandle::new(&ctx.handle, move buffer, style);
+        let handle = FontHandle::new_from_buffer(&ctx.handle, move buffer, style);
         let handle = if handle.is_ok() {
             result::unwrap(move handle)
         } else {
@@ -326,25 +322,34 @@ impl Font {
         return move result;
     }
 
-    priv fn get_azure_font() -> AzScaledFontRef {
+    // TODO: this should return a borrowed pointer, but I can't figure
+    // out why borrowck doesn't like my implementation.
+
+    priv fn get_azure_font(&self) -> AzScaledFontRef {
         // fast path: we've already created the azure font resource
         match self.azure_font {
-            Some(azfont) => return azfont,
+            Some(ref azfont) => return azfont.get_ref(),
             None => {}
         }
 
+        let mut scaled_font = self.create_azure_font();
+        self.azure_font = Some(move scaled_font);
+        // try again.
+        return self.get_azure_font();
+    }
+
+    #[cfg(target_os="macos")]
+    priv fn create_azure_font() -> ScaledFont {
         let ct_font = &self.handle.ctfont;
         let size = self.style.pt_size as AzFloat;
-        let scaled_font = azure::scaled_font::ScaledFont::new(self.backend, ct_font, size);
-
-        let azure_scaled_font;
-        unsafe {
-            azure_scaled_font = scaled_font.azure_scaled_font;
-            cast::forget(move scaled_font);
-        }
+        ScaledFont::new(self.backend, ct_font, size)
+    }
 
-        self.azure_font = Some(azure_scaled_font);
-        azure_scaled_font
+    #[cfg(target_os="linux")]
+    priv fn create_azure_font() -> ScaledFont {
+        let cairo_font = self.handle.face;
+        let size = self.style.pt_size as AzFloat;
+        ScaledFont::new(self.backend, cairo_font, size)
     }
 }
 
@@ -380,7 +385,7 @@ pub impl Font : FontMethods {
                              AzReleaseColorPattern};
 
         let target = rctx.get_draw_target();
-        let azfont = self.get_azure_font();
+        let azfontref = self.get_azure_font();
         let pattern = ColorPattern(color);
         let azure_pattern = pattern.azure_color_pattern;
         assert azure_pattern.is_not_null();
@@ -418,7 +423,7 @@ pub impl Font : FontMethods {
 
         // TODO(Issue #64): this call needs to move into azure_hl.rs
         AzDrawTargetFillGlyphs(target.azure_draw_target,
-                               azfont,
+                               azfontref,
                                ptr::to_unsafe_ptr(&glyphbuf),
                                azure_pattern,
                                ptr::to_unsafe_ptr(&options),

src/servo-gfx/font_context.rs

@@ -137,7 +137,7 @@ pub impl FontContext {
             },
             // TODO(Issue #174): implement by-platform-name font selectors.
             SelectorPlatformIdentifier(identifier) => { 
-                let result_handle = self.handle.create_font_from_identifier(identifier, copy desc.style);
+                let result_handle = self.handle.create_font_from_identifier(copy identifier, copy desc.style);
                 result::chain(move result_handle, |handle| {
                     Ok(Font::new_from_adopted_handle(&self, move handle, &desc.style, self.backend))
                 })

src/servo-gfx/font_list.rs

@@ -8,7 +8,7 @@ use send_map::{linear, SendMap};
 type FontListHandle/& = quartz::font_list::QuartzFontListHandle;
 
 #[cfg(target_os = "linux")]
-type FontListHandle/& = freetype::font_list::FreeTypeFontListHandle;
+type FontListHandle/& = fontconfig::font_list::FontconfigFontListHandle;
 
 pub impl FontListHandle {
     #[cfg(target_os = "macos")]
@@ -18,7 +18,7 @@ pub impl FontListHandle {
 
     #[cfg(target_os = "linux")]
     static pub fn new(fctx: &native::FontContextHandle) -> Result<FontListHandle, ()> {
-        Ok(freetype::font_list::FreeTypeFontListHandle::new(fctx))
+        Ok(fontconfig::font_list::FontconfigFontListHandle::new(fctx))
     }
 }
 

src/servo-gfx/fontconfig/font_list.rs

@@ -1,12 +1,27 @@
-pub struct FontconfigFontContextHandle {
-    ctx: (),
+extern mod freetype;
+extern mod fontconfig;
 
-    drop { }
+use fc = fontconfig;
+use ft = freetype;
+
+use gfx_font::FontHandle;
+use gfx_font_list::{FontEntry, FontFamily};
+
+use core::dvec::DVec;
+use core::send_map::{linear, SendMap};
+
+pub struct FontconfigFontListHandle {
+    fctx: (),
 }
 
-pub impl FontconfigFontContextHandle {
-    // this is a placeholder.
-    static pub fn new() -> FontconfigFontContextHandle {
-        FontconfigFontContextHandle { ctx: () }
+pub impl FontconfigFontListHandle {
+    static pub fn new(_fctx: &native::FontContextHandle) -> FontconfigFontListHandle {
+        FontconfigFontListHandle { fctx: () }
     }
-}
+
+    fn get_available_families(&const self,
+                              _fctx: &native::FontContextHandle)
+                           -> linear::LinearMap<~str, @FontFamily> {
+        fail;
+    }
+}

src/servo-gfx/freetype/font.rs

@@ -1,17 +1,35 @@
 extern mod freetype;
 
-use font::{FontMetrics, FractionalPixel};
-use font_context::FreeTypeFontContext;
+use font_context::FreeTypeFontContextHandle;
+use gfx_font::{
+    CSSFontWeight,
+    FontHandle,
+    FontHandleMethods,
+    FontMetrics,
+    FontTableTag,
+    FractionalPixel,
+    SpecifiedFontStyle,
+    UsedFontStyle,
+};
 use geometry::Au;
 use text::glyph::GlyphIndex;
 use text::util::{float_to_fixed, fixed_to_float};
 
-use cast::reinterpret_cast;
-use ptr::{addr_of, null};
-use vec_as_buf = vec::as_imm_buf;
-
-use freetype::{ FT_Error, FT_Library, FT_Face, FT_Long, FT_ULong, FT_Size, FT_SizeRec,
-               FT_UInt, FT_GlyphSlot, FT_Size_Metrics, FT_FaceRec, FT_F26Dot6 };
+use freetype::{
+    FTErrorMethods,
+    FT_Error,
+    FT_F26Dot6,
+    FT_Face, 
+    FT_FaceRec, 
+    FT_GlyphSlot, 
+    FT_Library,
+    FT_Long,
+    FT_ULong,
+    FT_Size,
+    FT_SizeRec,
+    FT_UInt,
+    FT_Size_Metrics,
+};
 use freetype::bindgen::{
     FT_Init_FreeType,
     FT_Done_FreeType,
@@ -46,27 +64,70 @@ pub struct FreeTypeFontHandle {
 }
 
 pub impl FreeTypeFontHandle {
-    static pub fn new(fctx: &FreeTypeFontContext,
-                      buf: ~[u8], pt_size: float) -> Result<FreeTypeFontHandle, ()> {
-        let ft_ctx = fctx.ctx;
-        assert ft_ctx.is_not_null();
-        let face_result: Result<FT_Face,()> = vec_as_buf(buf, |cbuf, _len| {
-            if FT_New_Memory_Face(ft_ctx, cbuf, (*buf).len() as FT_Long,
-                                  0 as FT_Long, addr_of(&face)).succeeded() {
-                let res = FT_Set_Char_Size(face, // the face
-                                           float_to_fixed_ft(pt_size) as FT_F26Dot6, // char width
-                                           float_to_fixed_ft(pt_size) as FT_F26Dot6, // char height
-                                           72, // horiz. DPI
-                                           72); // vert. DPI
-                if !res.succeeded() { fail ~"unable to set font char size" }
-                Ok(face)
-            } else {
-                Err(())
-            }
-        });
-        return do result::chain(face_result) |face| {
-            Ok(FreeTypeFontHandle { face: face, buf: move buf })
+    static pub fn new_from_buffer(fctx: &FreeTypeFontContextHandle,
+                      buf: ~[u8], style: &SpecifiedFontStyle) -> Result<FreeTypeFontHandle, ()> {
+        let ft_ctx: FT_Library = fctx.ctx;
+        if ft_ctx.is_null() { return Err(()); }
+
+        let face_result = do vec::as_imm_buf(buf) |bytes: *u8, len: uint| {
+            create_face_from_buffer(ft_ctx, bytes, len, style.pt_size)
+        };
+
+        // TODO: this could be more simply written as result::chain
+        // and moving buf into the struct ctor, but cant' move out of
+        // captured binding.
+        return match face_result {
+            Ok(face) => Ok(FreeTypeFontHandle { face: face, buf: move buf }),
+            Err(()) => Err(())
         };
+
+         fn create_face_from_buffer(lib: FT_Library,
+                                    cbuf: *u8, cbuflen: uint, pt_size: float) 
+             -> Result<FT_Face, ()> {
+
+             let mut face: FT_Face = ptr::null();
+             let face_index = 0 as FT_Long;
+             let result = FT_New_Memory_Face(lib, cbuf, cbuflen as FT_Long,
+                                             face_index, ptr::to_unsafe_ptr(&face));
+
+             if !result.succeeded() || face.is_null() {
+                 return Err(());
+             }
+             let char_width = float_to_fixed_ft(pt_size) as FT_F26Dot6;
+             let char_height = float_to_fixed_ft(pt_size) as FT_F26Dot6;
+             let h_dpi = 72;
+             let v_dpi = 72;
+
+             let result = FT_Set_Char_Size(face, char_width, char_height, h_dpi, v_dpi);
+             if !result.succeeded() { return Err(()); }
+
+             Ok(face)
+         }
+    }
+}
+
+pub impl FreeTypeFontHandle : FontHandleMethods {
+
+    // an identifier usable by FontContextHandle to recreate this FontHandle.
+    pure fn face_identifier() -> ~str {
+        fail;
+    }
+    pure fn family_name() -> ~str {
+        fail;
+    }
+    pure fn face_name() -> ~str {
+        fail;
+    }
+    pure fn is_italic() -> bool {
+        fail;
+    }
+    pure fn boldness() -> CSSFontWeight {
+        fail;
+    }
+
+    fn clone_with_style(_fctx: &native::FontContextHandle,
+                        _style: &UsedFontStyle) -> Result<FontHandle, ()> {
+        fail;
     }
 
     pub fn glyph_index(codepoint: char) -> Option<GlyphIndex> {
@@ -86,7 +147,7 @@ pub impl FreeTypeFontHandle {
         if res.succeeded() {
             unsafe {
                 let void_glyph = (*self.face).glyph;
-                let slot: FT_GlyphSlot = reinterpret_cast(&void_glyph);
+                let slot: FT_GlyphSlot = cast::transmute(void_glyph);
                 assert slot.is_not_null();
                 debug!("metrics: %?", (*slot).metrics);
                 let advance = (*slot).metrics.horiAdvance;
@@ -123,6 +184,12 @@ pub impl FreeTypeFontHandle {
         }
     }
 
+    fn get_table_for_tag(_tag: FontTableTag) -> Option<~[u8]> {
+        fail;
+    }
+}
+
+pub impl FreeTypeFontHandle {
     priv fn get_face_rec() -> &self/FT_FaceRec unsafe {
         &(*self.face)
     }
@@ -145,11 +212,3 @@ pub impl FreeTypeFontHandle {
         return geometry::from_frac_px(value * x_scale);
     }
 }
-
-trait FTErrorMethods {
-    fn succeeded() -> bool;
-}
-
-impl FT_Error : FTErrorMethods {
-    fn succeeded() -> bool { self == 0 as FT_Error }
-}