glyph_pos.cpp File Reference

#include "gm/gm.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkColor.h"
#include "include/core/SkFont.h"
#include "include/core/SkFontTypes.h"
#include "include/core/SkMatrix.h"
#include "include/core/SkPaint.h"
#include "include/core/SkRect.h"
#include "include/core/SkScalar.h"
#include "include/core/SkTypeface.h"
#include "include/core/SkTypes.h"
#include "tools/ToolUtils.h"
#include "tools/fonts/FontToolUtils.h"

Go to the source code of this file.

Functions
static void	drawTestCase (SkCanvas *canvas, SkScalar textScale, SkScalar strokeWidth, SkPaint::Style strokeStyle)
static void	draw_gm (SkCanvas *canvas, SkScalar strokeWidth, SkPaint::Style strokeStyle)
	DEF_SIMPLE_GM (glyph_pos_h_b, c, 800, 600)
	DEF_SIMPLE_GM (glyph_pos_n_b, c, 800, 600)
	DEF_SIMPLE_GM (glyph_pos_h_s, c, 800, 600)
	DEF_SIMPLE_GM (glyph_pos_n_s, c, 800, 600)
	DEF_SIMPLE_GM (glyph_pos_h_f, c, 800, 600)
	DEF_SIMPLE_GM (glyph_pos_n_f, c, 800, 600)

Variables
constexpr SkScalar	kTextHeight = 14.0f
constexpr char	kText [] = "Proportional Hamburgefons #% fi"

Function Documentation

DEF_SIMPLE_GM() [1/6]

DEF_SIMPLE_GM	(	glyph_pos_h_b	,
		c	,
		800	,
		600
	)

Definition at line 150 of file glyph_pos.cpp.

                                          {
    draw_gm(c, 0.0f, SkPaint::kStrokeAndFill_Style);
}

DEF_SIMPLE_GM() [2/6]

DEF_SIMPLE_GM	(	glyph_pos_h_f	,
		c	,
		800	,
		600
	)

Definition at line 162 of file glyph_pos.cpp.

                                          {
    draw_gm(c, 0.0f, SkPaint::kFill_Style);
}

DEF_SIMPLE_GM() [3/6]

DEF_SIMPLE_GM	(	glyph_pos_h_s	,
		c	,
		800	,
		600
	)

Definition at line 156 of file glyph_pos.cpp.

                                          {
    draw_gm(c, 0.0f, SkPaint::kStroke_Style);
}

DEF_SIMPLE_GM() [4/6]

DEF_SIMPLE_GM	(	glyph_pos_n_b	,
		c	,
		800	,
		600
	)

Definition at line 153 of file glyph_pos.cpp.

                                          {
    draw_gm(c, 1.2f, SkPaint::kStrokeAndFill_Style);
}

DEF_SIMPLE_GM() [5/6]

DEF_SIMPLE_GM	(	glyph_pos_n_f	,
		c	,
		800	,
		600
	)

Definition at line 165 of file glyph_pos.cpp.

                                          {
    draw_gm(c, 1.2f, SkPaint::kFill_Style);
}

DEF_SIMPLE_GM() [6/6]

DEF_SIMPLE_GM	(	glyph_pos_n_s	,
		c	,
		800	,
		600
	)

Definition at line 159 of file glyph_pos.cpp.

                                          {
    draw_gm(c, 1.2f, SkPaint::kStroke_Style);
}

draw_gm()

static void draw_gm ( SkCanvas *  canvas, SkScalar  strokeWidth, SkPaint::Style  strokeStyle  )

static

Definition at line 35 of file glyph_pos.cpp.

                                              {
    // There's a black pixel at 40, 40 for reference.
    canvas->drawPoint(40, 40, SkPaint());
 
    // Two reference images.
    canvas->translate(50.0f, 50.0f);
    drawTestCase(canvas, 1.0f, strokeWidth, strokeStyle);
 
    canvas->translate(0.0f, 50.0f);
    drawTestCase(canvas, 3.0f, strokeWidth, strokeStyle);
 
    // Uniform scaling test.
    canvas->translate(0.0f, 100.0f);
    canvas->save();
    canvas->scale(3.0f, 3.0f);
    drawTestCase(canvas, 1.0f, strokeWidth, strokeStyle);
    canvas->restore();
 
    // Non-uniform scaling test.
    canvas->translate(0.0f, 100.0f);
    canvas->save();
    canvas->scale(3.0f, 6.0f);
    drawTestCase(canvas, 1.0f, strokeWidth, strokeStyle);
    canvas->restore();
 
    // Skew test.
    canvas->translate(0.0f, 80.0f);
    canvas->save();
    canvas->scale(3.0f, 3.0f);
    SkMatrix skew;
    skew.setIdentity();
    skew.setSkewX(8.0f / 25.0f);
    skew.setSkewY(2.0f / 25.0f);
    canvas->concat(skew);
    drawTestCase(canvas, 1.0f, strokeWidth, strokeStyle);
    canvas->restore();
 
    // Perspective test.
    canvas->translate(0.0f, 80.0f);
    canvas->save();
    SkMatrix perspective;
    perspective.setIdentity();
    perspective.setPerspX(-SkScalarInvert(340));
    perspective.setSkewX(8.0f / 25.0f);
    perspective.setSkewY(2.0f / 25.0f);
 
    canvas->concat(perspective);
    drawTestCase(canvas, 1.0f, strokeWidth, strokeStyle);
    canvas->restore();
}

drawTestCase()

static void drawTestCase ( SkCanvas *  canvas, SkScalar  textScale, SkScalar  strokeWidth, SkPaint::Style  strokeStyle  )

static

Definition at line 88 of file glyph_pos.cpp.

                                                   {
    SkPaint paint;
    paint.setColor(SK_ColorBLACK);
    paint.setAntiAlias(true);
    paint.setStrokeWidth(strokeWidth);
    paint.setStyle(strokeStyle);
 
    SkFont font(ToolUtils::DefaultPortableTypeface(), kTextHeight * textScale);
 
    // This demonstrates that we can not measure the text if
    // there's a device transform. The canvas total matrix will
    // end up being a device transform.
    bool drawRef = !(canvas->getLocalToDeviceAs3x3().getType() &
                     ~(SkMatrix::kIdentity_Mask | SkMatrix::kTranslate_Mask));
 
    SkRect bounds;
    if (drawRef) {
        SkScalar advance = font.measureText(kText, sizeof(kText) - 1, SkTextEncoding::kUTF8,
                                            &bounds, &paint);
 
        paint.setStrokeWidth(0.0f);
        paint.setStyle(SkPaint::kStroke_Style);
 
        // Green box is the measured text bounds.
        paint.setColor(SK_ColorGREEN);
        canvas->drawRect(bounds, paint);
 
        // Red line is the measured advance from the 0,0 of the text position.
        paint.setColor(SK_ColorRED);
        canvas->drawLine(0.0f, 0.0f, advance, 0.0f, paint);
    }
 
    // Black text is the testcase, eg. the text.
    paint.setColor(SK_ColorBLACK);
    paint.setStrokeWidth(strokeWidth);
    paint.setStyle(strokeStyle);
    canvas->drawSimpleText(kText, sizeof(kText) - 1, SkTextEncoding::kUTF8,
                           0.0f, 0.0f, font, paint);
 
    if (drawRef) {
        const size_t len = sizeof(kText) - 1;
        SkGlyphID glyphs[len];
        const int count = font.textToGlyphs(kText, len, SkTextEncoding::kUTF8, glyphs, len);
        SkScalar widths[len]; // len is conservative. we really only need 'count'
        font.getWidthsBounds(glyphs, count, widths, nullptr, &paint);
 
        paint.setStrokeWidth(0.0f);
        paint.setStyle(SkPaint::kStroke_Style);
 
        // Magenta lines are the positions for the characters.
        paint.setColor(SK_ColorMAGENTA);
        SkScalar w = 0;
        for (size_t i = 0; i < sizeof(kText) - 1; ++i) {
            canvas->drawLine(w, 0.0f, w, 5.0f, paint);
            w += widths[i];
        }
    }
}

Variable Documentation

kText

constexpr char kText[] = "Proportional Hamburgefons #% fi"

constexpr

Definition at line 28 of file glyph_pos.cpp.

kTextHeight

constexpr SkScalar kTextHeight = 14.0f

constexpr

Definition at line 27 of file glyph_pos.cpp.