gecko-dev/servo/components/gfx/render_context.rs
2014-10-21 19:54:37 -06:00

420 lines
19 KiB
Rust

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
use font_context::FontContext;
use style::computed_values::border_style;
use azure::azure_hl::{B8G8R8A8, A8, Color, ColorPattern, ColorPatternRef, DrawOptions};
use azure::azure_hl::{DrawSurfaceOptions, DrawTarget, Linear, SourceOp, StrokeOptions};
use azure::AZ_CAP_BUTT;
use azure::AzFloat;
use geom::point::Point2D;
use geom::rect::Rect;
use geom::size::Size2D;
use geom::side_offsets::SideOffsets2D;
use libc::types::common::c99::uint16_t;
use libc::size_t;
use png::{RGB8, RGBA8, K8, KA8};
use servo_net::image::base::Image;
use servo_util::geometry::Au;
use sync::Arc;
pub struct RenderContext<'a> {
pub draw_target: &'a DrawTarget,
pub font_ctx: &'a mut Box<FontContext>,
/// The rectangle that this context encompasses in page coordinates.
pub page_rect: Rect<f32>,
/// The rectangle that this context encompasses in screen coordinates (pixels).
pub screen_rect: Rect<uint>,
}
enum Direction {
Top,
Left,
Right,
Bottom
}
enum DashSize {
DottedBorder = 1,
DashedBorder = 3
}
impl<'a> RenderContext<'a> {
pub fn get_draw_target(&self) -> &'a DrawTarget {
self.draw_target
}
pub fn draw_solid_color(&self, bounds: &Rect<Au>, color: Color) {
self.draw_target.make_current();
self.draw_target.fill_rect(&bounds.to_azure_rect(),
ColorPatternRef(&ColorPattern::new(color)),
None);
}
pub fn draw_border(&self,
bounds: &Rect<Au>,
border: SideOffsets2D<Au>,
color: SideOffsets2D<Color>,
style: SideOffsets2D<border_style::T>) {
let border = border.to_float_px();
self.draw_target.make_current();
self.draw_border_segment(Top, bounds, border, color, style);
self.draw_border_segment(Right, bounds, border, color, style);
self.draw_border_segment(Bottom, bounds, border, color, style);
self.draw_border_segment(Left, bounds, border, color, style);
}
pub fn draw_line(&self,
bounds: &Rect<Au>,
color: Color,
style: border_style::T) {
self.draw_target.make_current();
self.draw_line_segment(bounds, color, style);
}
pub fn draw_push_clip(&self, bounds: &Rect<Au>) {
let rect = bounds.to_azure_rect();
let path_builder = self.draw_target.create_path_builder();
let left_top = Point2D(rect.origin.x, rect.origin.y);
let right_top = Point2D(rect.origin.x + rect.size.width, rect.origin.y);
let left_bottom = Point2D(rect.origin.x, rect.origin.y + rect.size.height);
let right_bottom = Point2D(rect.origin.x + rect.size.width, rect.origin.y + rect.size.height);
path_builder.move_to(left_top);
path_builder.line_to(right_top);
path_builder.line_to(right_bottom);
path_builder.line_to(left_bottom);
let path = path_builder.finish();
self.draw_target.push_clip(&path);
}
pub fn draw_pop_clip(&self) {
self.draw_target.pop_clip();
}
pub fn draw_image(&self, bounds: Rect<Au>, image: Arc<Box<Image>>) {
let size = Size2D(image.width as i32, image.height as i32);
let (pixel_width, pixels, source_format) = match image.pixels {
RGBA8(ref pixels) => (4, pixels.as_slice(), B8G8R8A8),
K8(ref pixels) => (1, pixels.as_slice(), A8),
RGB8(_) => fail!("RGB8 color type not supported"),
KA8(_) => fail!("KA8 color type not supported"),
};
let stride = image.width * pixel_width;
self.draw_target.make_current();
let draw_target_ref = &self.draw_target;
let azure_surface = draw_target_ref.create_source_surface_from_data(pixels,
size,
stride as i32,
source_format);
let source_rect = Rect(Point2D(0u as AzFloat, 0u as AzFloat),
Size2D(image.width as AzFloat, image.height as AzFloat));
let dest_rect = bounds.to_azure_rect();
let draw_surface_options = DrawSurfaceOptions::new(Linear, true);
let draw_options = DrawOptions::new(1.0f64 as AzFloat, 0);
draw_target_ref.draw_surface(azure_surface,
dest_rect,
source_rect,
draw_surface_options,
draw_options);
}
pub fn clear(&self) {
let pattern = ColorPattern::new(Color::new(0.0, 0.0, 0.0, 0.0));
let rect = Rect(Point2D(self.page_rect.origin.x as AzFloat,
self.page_rect.origin.y as AzFloat),
Size2D(self.screen_rect.size.width as AzFloat,
self.screen_rect.size.height as AzFloat));
let mut draw_options = DrawOptions::new(1.0, 0);
draw_options.set_composition_op(SourceOp);
self.draw_target.make_current();
self.draw_target.fill_rect(&rect, ColorPatternRef(&pattern), Some(&draw_options));
}
fn draw_border_segment(&self, direction: Direction, bounds: &Rect<Au>, border: SideOffsets2D<f32>, color: SideOffsets2D<Color>, style: SideOffsets2D<border_style::T>) {
let (style_select, color_select) = match direction {
Top => (style.top, color.top),
Left => (style.left, color.left),
Right => (style.right, color.right),
Bottom => (style.bottom, color.bottom)
};
match style_select{
border_style::none => {
}
border_style::hidden => {
}
//FIXME(sammykim): This doesn't work with dash_pattern and cap_style well. I referred firefox code.
border_style::dotted => {
self.draw_dashed_border_segment(direction, bounds, border, color_select, DottedBorder);
}
border_style::dashed => {
self.draw_dashed_border_segment(direction, bounds, border, color_select, DashedBorder);
}
border_style::solid => {
self.draw_solid_border_segment(direction,bounds,border,color_select);
}
border_style::double => {
self.draw_double_border_segment(direction, bounds, border, color_select);
}
border_style::groove | border_style::ridge => {
self.draw_groove_ridge_border_segment(direction, bounds, border, color_select, style_select);
}
border_style::inset | border_style::outset => {
self.draw_inset_outset_border_segment(direction, bounds, border, style_select, color_select);
}
}
}
fn draw_line_segment(&self, bounds: &Rect<Au>, color: Color, style: border_style::T) {
let border = SideOffsets2D::new_all_same(bounds.size.width).to_float_px();
match style{
border_style::none | border_style::hidden => {}
border_style::dotted => {
self.draw_dashed_border_segment(Right, bounds, border, color, DottedBorder);
}
border_style::dashed => {
self.draw_dashed_border_segment(Right, bounds, border, color, DashedBorder);
}
border_style::solid => {
self.draw_solid_border_segment(Right,bounds,border,color);
}
border_style::double => {
self.draw_double_border_segment(Right, bounds, border, color);
}
border_style::groove | border_style::ridge => {
self.draw_groove_ridge_border_segment(Right, bounds, border, color, style);
}
border_style::inset | border_style::outset => {
self.draw_inset_outset_border_segment(Right, bounds, border, style, color);
}
}
}
fn draw_border_path(&self,
bounds: Rect<f32>,
direction: Direction,
border: SideOffsets2D<f32>,
color: Color) {
let left_top = bounds.origin;
let right_top = left_top + Point2D(bounds.size.width, 0.0);
let left_bottom = left_top + Point2D(0.0, bounds.size.height);
let right_bottom = left_top + Point2D(bounds.size.width, bounds.size.height);
let draw_opts = DrawOptions::new(1.0, 0);
let path_builder = self.draw_target.create_path_builder();
match direction {
Top => {
path_builder.move_to(left_top);
path_builder.line_to(right_top);
path_builder.line_to(right_top + Point2D(-border.right, border.top));
path_builder.line_to(left_top + Point2D(border.left, border.top));
}
Left => {
path_builder.move_to(left_top);
path_builder.line_to(left_top + Point2D(border.left, border.top));
path_builder.line_to(left_bottom + Point2D(border.left, -border.bottom));
path_builder.line_to(left_bottom);
}
Right => {
path_builder.move_to(right_top);
path_builder.line_to(right_bottom);
path_builder.line_to(right_bottom + Point2D(-border.right, -border.bottom));
path_builder.line_to(right_top + Point2D(-border.right, border.top));
}
Bottom => {
path_builder.move_to(left_bottom);
path_builder.line_to(left_bottom + Point2D(border.left, -border.bottom));
path_builder.line_to(right_bottom + Point2D(-border.right, -border.bottom));
path_builder.line_to(right_bottom);
}
}
let path = path_builder.finish();
self.draw_target.fill(&path, &ColorPattern::new(color), &draw_opts);
}
fn draw_dashed_border_segment(&self,
direction: Direction,
bounds: &Rect<Au>,
border: SideOffsets2D<f32>,
color: Color,
dash_size: DashSize) {
let rect = bounds.to_azure_rect();
let draw_opts = DrawOptions::new(1u as AzFloat, 0 as uint16_t);
let mut stroke_opts = StrokeOptions::new(0u as AzFloat, 10u as AzFloat);
let mut dash: [AzFloat, ..2] = [0u as AzFloat, 0u as AzFloat];
stroke_opts.set_cap_style(AZ_CAP_BUTT as u8);
let border_width = match direction {
Top => border.top,
Left => border.left,
Right => border.right,
Bottom => border.bottom
};
stroke_opts.line_width = border_width;
dash[0] = border_width * (dash_size as int) as AzFloat;
dash[1] = border_width * (dash_size as int) as AzFloat;
stroke_opts.mDashPattern = dash.as_mut_ptr();
stroke_opts.mDashLength = dash.len() as size_t;
let (start, end) = match direction {
Top => {
let y = rect.origin.y + border.top * 0.5;
let start = Point2D(rect.origin.x, y);
let end = Point2D(rect.origin.x + rect.size.width, y);
(start, end)
}
Left => {
let x = rect.origin.x + border.left * 0.5;
let start = Point2D(x, rect.origin.y + rect.size.height);
let end = Point2D(x, rect.origin.y + border.top);
(start, end)
}
Right => {
let x = rect.origin.x + rect.size.width - border.right * 0.5;
let start = Point2D(x, rect.origin.y);
let end = Point2D(x, rect.origin.y + rect.size.height);
(start, end)
}
Bottom => {
let y = rect.origin.y + rect.size.height - border.bottom * 0.5;
let start = Point2D(rect.origin.x + rect.size.width, y);
let end = Point2D(rect.origin.x + border.left, y);
(start, end)
}
};
self.draw_target.stroke_line(start,
end,
&ColorPattern::new(color),
&stroke_opts,
&draw_opts);
}
fn draw_solid_border_segment(&self, direction: Direction, bounds: &Rect<Au>, border: SideOffsets2D<f32>, color: Color) {
let rect = bounds.to_azure_rect();
self.draw_border_path(rect, direction, border, color);
}
fn get_scaled_bounds(&self,
bounds: &Rect<Au>,
border: SideOffsets2D<f32>,
shrink_factor: f32) -> Rect<f32> {
let rect = bounds.to_azure_rect();
let scaled_border = SideOffsets2D::new(shrink_factor * border.top,
shrink_factor * border.right,
shrink_factor * border.bottom,
shrink_factor * border.left);
let left_top = Point2D(rect.origin.x, rect.origin.y);
let scaled_left_top = left_top + Point2D(scaled_border.left,
scaled_border.top);
return Rect(scaled_left_top,
Size2D(rect.size.width - 2.0 * scaled_border.right, rect.size.height - 2.0 * scaled_border.bottom));
}
fn scale_color(&self, color: Color, scale_factor: f32) -> Color {
return Color::new(color.r * scale_factor, color.g * scale_factor, color.b * scale_factor, color.a);
}
fn draw_double_border_segment(&self, direction: Direction, bounds: &Rect<Au>, border: SideOffsets2D<f32>, color: Color) {
let scaled_border = SideOffsets2D::new((1.0/3.0) * border.top,
(1.0/3.0) * border.right,
(1.0/3.0) * border.bottom,
(1.0/3.0) * border.left);
let inner_scaled_bounds = self.get_scaled_bounds(bounds, border, 2.0/3.0);
// draw the outer portion of the double border.
self.draw_solid_border_segment(direction, bounds, scaled_border, color);
// draw the inner portion of the double border.
self.draw_border_path(inner_scaled_bounds, direction, scaled_border, color);
}
fn draw_groove_ridge_border_segment(&self,
direction: Direction,
bounds: &Rect<Au>,
border: SideOffsets2D<f32>,
color: Color,
style: border_style::T) {
// original bounds as a Rect<f32>, with no scaling.
let original_bounds = self.get_scaled_bounds(bounds, border, 0.0);
// shrink the bounds by 1/2 of the border, leaving the innermost 1/2 of the border
let inner_scaled_bounds = self.get_scaled_bounds(bounds, border, 0.5);
let scaled_border = SideOffsets2D::new(0.5 * border.top,
0.5 * border.right,
0.5 * border.bottom,
0.5 * border.left);
let is_groove = match style {
border_style::groove => true,
border_style::ridge => false,
_ => fail!("invalid border style")
};
let darker_color = self.scale_color(color, if is_groove { 1.0/3.0 } else { 2.0/3.0 });
let (outer_color, inner_color) = match (direction, is_groove) {
(Top, true) | (Left, true) | (Right, false) | (Bottom, false) => (darker_color, color),
(Top, false) | (Left, false) | (Right, true) | (Bottom, true) => (color, darker_color)
};
// outer portion of the border
self.draw_border_path(original_bounds, direction, scaled_border, outer_color);
// inner portion of the border
self.draw_border_path(inner_scaled_bounds, direction, scaled_border, inner_color);
}
fn draw_inset_outset_border_segment(&self,
direction: Direction,
bounds: &Rect<Au>,
border: SideOffsets2D<f32>,
style: border_style::T,
color: Color) {
let is_inset = match style {
border_style::inset => true,
border_style::outset => false,
_ => fail!("invalid border style")
};
// original bounds as a Rect<f32>
let original_bounds = self.get_scaled_bounds(bounds, border, 0.0);
// select and scale the color appropriately.
let scaled_color = match direction {
Top => self.scale_color(color, if is_inset { 2.0/3.0 } else { 1.0 }),
Left => self.scale_color(color, if is_inset { 1.0/6.0 } else { 0.5 }),
Right | Bottom => self.scale_color(color, if is_inset { 1.0 } else { 2.0/3.0 })
};
self.draw_border_path(original_bounds, direction, border, scaled_color);
}
}
trait ToAzureRect {
fn to_azure_rect(&self) -> Rect<AzFloat>;
}
impl ToAzureRect for Rect<Au> {
fn to_azure_rect(&self) -> Rect<AzFloat> {
Rect(Point2D(self.origin.x.to_nearest_px() as AzFloat,
self.origin.y.to_nearest_px() as AzFloat),
Size2D(self.size.width.to_nearest_px() as AzFloat,
self.size.height.to_nearest_px() as AzFloat))
}
}
trait ToSideOffsetsPx {
fn to_float_px(&self) -> SideOffsets2D<AzFloat>;
}
impl ToSideOffsetsPx for SideOffsets2D<Au> {
fn to_float_px(&self) -> SideOffsets2D<AzFloat> {
SideOffsets2D::new(self.top.to_nearest_px() as AzFloat,
self.right.to_nearest_px() as AzFloat,
self.bottom.to_nearest_px() as AzFloat,
self.left.to_nearest_px() as AzFloat)
}
}