/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*- * 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/. */ #include "gfxFontMissingGlyphs.h" #include "gfxUtils.h" #include "mozilla/gfx/2D.h" #include "mozilla/gfx/Helpers.h" #include "mozilla/gfx/PathHelpers.h" #include "mozilla/RefPtr.h" #include "nsDeviceContext.h" #include "nsLayoutUtils.h" using namespace mozilla; using namespace mozilla::gfx; #define CHAR_BITS(b00, b01, b02, b10, b11, b12, b20, b21, b22, b30, b31, b32, b40, b41, b42) \ ((b00 << 0) | (b01 << 1) | (b02 << 2) | (b10 << 3) | (b11 << 4) | (b12 << 5) | \ (b20 << 6) | (b21 << 7) | (b22 << 8) | (b30 << 9) | (b31 << 10) | (b32 << 11) | \ (b40 << 12) | (b41 << 13) | (b42 << 14)) static const uint16_t glyphMicroFont[16] = { CHAR_BITS(0, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0), CHAR_BITS(0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0), CHAR_BITS(1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1), CHAR_BITS(1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1), CHAR_BITS(1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1), CHAR_BITS(1, 1, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 1, 1), CHAR_BITS(1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1), CHAR_BITS(1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1), CHAR_BITS(0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0), CHAR_BITS(1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1), CHAR_BITS(1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1), CHAR_BITS(1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0), CHAR_BITS(0, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 1), CHAR_BITS(1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0), CHAR_BITS(1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1), CHAR_BITS(1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0) }; /* Parameters that control the rendering of hexboxes. They look like this: BMP codepoints non-BMP codepoints (U+0000 - U+FFFF) (U+10000 - U+10FFFF) +---------+ +-------------+ | | | | | HHH HHH | | HHH HHH HHH | | HHH HHH | | HHH HHH HHH | | HHH HHH | | HHH HHH HHH | | HHH HHH | | HHH HHH HHH | | HHH HHH | | HHH HHH HHH | | | | | | HHH HHH | | HHH HHH HHH | | HHH HHH | | HHH HHH HHH | | HHH HHH | | HHH HHH HHH | | HHH HHH | | HHH HHH HHH | | HHH HHH | | HHH HHH HHH | | | | | +---------+ +-------------+ */ /** Width of a minifont glyph (see above) */ static const int MINIFONT_WIDTH = 3; /** Height of a minifont glyph (see above) */ static const int MINIFONT_HEIGHT = 5; /** * Gap between minifont glyphs (both horizontal and vertical) and also * the minimum desired gap between the box border and the glyphs */ static const int HEX_CHAR_GAP = 1; /** * The amount of space between the vertical edge of the glyphbox and the * box border. We make this nonzero so that when multiple missing glyphs * occur consecutively there's a gap between their rendered boxes. */ static const int BOX_HORIZONTAL_INSET = 1; /** The width of the border */ static const int BOX_BORDER_WIDTH = 1; /** * The scaling factor for the border opacity; this is multiplied by the current * opacity being used to draw the text. */ static const Float BOX_BORDER_OPACITY = 0.5; /** * Draw a single hex character using the current color. A nice way to do this * would be to fill in an A8 image surface and then use it as a mask * to paint the current color. Tragically this doesn't currently work with the * Quartz cairo backend which doesn't generally support masking with surfaces. * So for now we just paint a bunch of rectangles... */ static void DrawHexChar(uint32_t aDigit, const Point& aPt, DrawTarget& aDrawTarget, const Pattern &aPattern) { // To avoid the potential for seams showing between rects when we're under // a transform we concat all the rects into a PathBuilder and fill the // resulting Path (rather than using DrawTarget::FillRect). RefPtr builder = aDrawTarget.CreatePathBuilder(); uint32_t glyphBits = glyphMicroFont[aDigit]; for (int y = 0; y < MINIFONT_HEIGHT; ++y) { for (int x = 0; x < MINIFONT_WIDTH; ++x) { if (glyphBits & 1) { Rect r(aPt.x + x, aPt.y + y, 1, 1); MaybeSnapToDevicePixels(r, aDrawTarget, true); builder->MoveTo(r.TopLeft()); builder->LineTo(r.TopRight()); builder->LineTo(r.BottomRight()); builder->LineTo(r.BottomLeft()); builder->Close(); } glyphBits >>= 1; } } RefPtr path = builder->Finish(); aDrawTarget.Fill(path, aPattern); } void gfxFontMissingGlyphs::DrawMissingGlyph(uint32_t aChar, const Rect& aRect, DrawTarget& aDrawTarget, const Pattern& aPattern, uint32_t aAppUnitsPerDevPixel) { // If we're currently drawing with some kind of pattern, we just draw the // missing-glyph data in black. ColorPattern color = aPattern.GetType() == PatternType::COLOR ? static_cast(aPattern) : ColorPattern(ToDeviceColor(Color(0.f, 0.f, 0.f, 1.f))); // Stroke a rectangle so that the stroke's left edge is inset one pixel // from the left edge of the glyph box and the stroke's right edge // is inset one pixel from the right edge of the glyph box. Float halfBorderWidth = BOX_BORDER_WIDTH / 2.0; Float borderLeft = aRect.X() + BOX_HORIZONTAL_INSET + halfBorderWidth; Float borderRight = aRect.XMost() - BOX_HORIZONTAL_INSET - halfBorderWidth; Rect borderStrokeRect(borderLeft, aRect.Y() + halfBorderWidth, borderRight - borderLeft, aRect.Height() - 2.0 * halfBorderWidth); if (!borderStrokeRect.IsEmpty()) { ColorPattern adjustedColor = color; color.mColor.a *= BOX_BORDER_OPACITY; StrokeOptions strokeOptions(BOX_BORDER_WIDTH); aDrawTarget.StrokeRect(borderStrokeRect, adjustedColor, strokeOptions); } Point center = aRect.Center(); Float halfGap = HEX_CHAR_GAP / 2.f; Float top = -(MINIFONT_HEIGHT + halfGap); // We always want integer scaling, otherwise the "bitmap" glyphs will look // even uglier than usual when zoomed int32_t devPixelsPerCSSPx = std::max(1, nsDeviceContext::AppUnitsPerCSSPixel() / aAppUnitsPerDevPixel); AutoRestoreTransform autoRestoreTransform(&aDrawTarget); aDrawTarget.SetTransform( aDrawTarget.GetTransform().PreTranslate(center). PreScale(devPixelsPerCSSPx, devPixelsPerCSSPx)); if (aChar < 0x10000) { if (aRect.Width() >= 2 * (MINIFONT_WIDTH + HEX_CHAR_GAP) && aRect.Height() >= 2 * MINIFONT_HEIGHT + HEX_CHAR_GAP) { // Draw 4 digits for BMP Float left = -(MINIFONT_WIDTH + halfGap); DrawHexChar((aChar >> 12) & 0xF, Point(left, top), aDrawTarget, color); DrawHexChar((aChar >> 8) & 0xF, Point(halfGap, top), aDrawTarget, color); DrawHexChar((aChar >> 4) & 0xF, Point(left, halfGap), aDrawTarget, color); DrawHexChar(aChar & 0xF, Point(halfGap, halfGap), aDrawTarget, color); } } else { if (aRect.Width() >= 3 * (MINIFONT_WIDTH + HEX_CHAR_GAP) && aRect.Height() >= 2 * MINIFONT_HEIGHT + HEX_CHAR_GAP) { // Draw 6 digits for non-BMP Float first = -(MINIFONT_WIDTH * 1.5 + HEX_CHAR_GAP); Float second = -(MINIFONT_WIDTH / 2.0); Float third = (MINIFONT_WIDTH / 2.0 + HEX_CHAR_GAP); DrawHexChar((aChar >> 20) & 0xF, Point(first, top), aDrawTarget, color); DrawHexChar((aChar >> 16) & 0xF, Point(second, top), aDrawTarget, color); DrawHexChar((aChar >> 12) & 0xF, Point(third, top), aDrawTarget, color); DrawHexChar((aChar >> 8) & 0xF, Point(first, halfGap), aDrawTarget, color); DrawHexChar((aChar >> 4) & 0xF, Point(second, halfGap), aDrawTarget, color); DrawHexChar(aChar & 0xF, Point(third, halfGap), aDrawTarget, color); } } } Float gfxFontMissingGlyphs::GetDesiredMinWidth(uint32_t aChar, uint32_t aAppUnitsPerDevPixel) { /** * The minimum desired width for a missing-glyph glyph box. I've laid it out * like this so you can see what goes where. */ Float width = BOX_HORIZONTAL_INSET + BOX_BORDER_WIDTH + HEX_CHAR_GAP + MINIFONT_WIDTH + HEX_CHAR_GAP + MINIFONT_WIDTH + ((aChar < 0x10000) ? 0 : HEX_CHAR_GAP + MINIFONT_WIDTH) + HEX_CHAR_GAP + BOX_BORDER_WIDTH + BOX_HORIZONTAL_INSET; // Note that this will give us floating-point division, so the width will // -not- be snapped to integer multiples of its basic pixel value width *= Float(nsDeviceContext::AppUnitsPerCSSPixel()) / aAppUnitsPerDevPixel; return width; }