skia2/gm/daa.cpp
Mike Reed 92f6eb1602 use pathbuilder
Change-Id: I2bca419a3273a9cc8a984b0f4159f518968c6652
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/313077
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
2020-08-25 16:29:48 +00:00

121 lines
3.8 KiB
C++

/*
* Copyright 2018 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "gm/gm.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkColor.h"
#include "include/core/SkFont.h"
#include "include/core/SkPaint.h"
#include "include/core/SkPathBuilder.h"
#include "include/core/SkPoint.h"
#include "include/core/SkTypes.h"
// This GM shows off a flaw in delta-based rasterizers (DAA, CCPR, etc.).
// See also the bottom of dashing4 and skia:6886.
static const int K = 49;
DEF_SIMPLE_GM(daa, canvas, K+350, 5*K) {
SkPaint paint;
paint.setAntiAlias(true);
{
paint.setColor(SK_ColorBLACK);
canvas->drawString("Should be a green square with no red showing through.",
K*1.5f, K*0.5f, SkFont(), paint);
paint.setColor(SK_ColorRED);
canvas->drawRect({0,0,K,K}, paint);
SkPoint tri1[] = {{0,0},{K,K},{0,K},{0,0}};
SkPoint tri2[] = {{0,0},{K,K},{K,0},{0,0}};
SkPath path = SkPathBuilder().addPolygon(tri1, SK_ARRAY_COUNT(tri1), false)
.addPolygon(tri2, SK_ARRAY_COUNT(tri2), false)
.detach();
paint.setColor(SK_ColorGREEN);
canvas->drawPath(path, paint);
}
canvas->translate(0,K);
{
paint.setColor(SK_ColorBLACK);
canvas->drawString("Adjacent rects, two draws. Blue then green, no red?",
K*1.5f, K*0.5f, SkFont(), paint);
paint.setColor(SK_ColorRED);
canvas->drawRect({0,0,K,K}, paint);
{
SkPath path = SkPath::Polygon({{0,0},{0,K},{K*0.5f,K},{K*0.5f,0}}, false);
paint.setColor(SK_ColorBLUE);
canvas->drawPath(path, paint);
}
{
SkPath path = SkPath::Polygon({{K*0.5f,0},{K*0.5f,K},{K,K},{K,0}}, false);
paint.setColor(SK_ColorGREEN);
canvas->drawPath(path, paint);
}
}
canvas->translate(0,K);
{
paint.setColor(SK_ColorBLACK);
canvas->drawString("Adjacent rects, wound together. All green?",
K*1.5f, K*0.5f, SkFont(), paint);
paint.setColor(SK_ColorRED);
canvas->drawRect({0,0,K,K}, paint);
{
SkPath path = SkPathBuilder().addPolygon({{0,0},{0,K},{K*0.5f,K},{K*0.5f,0}}, false)
.addPolygon({{K*0.5f,0},{K*0.5f,K},{K,K},{K,0}}, false)
.detach();
paint.setColor(SK_ColorGREEN);
canvas->drawPath(path, paint);
}
}
canvas->translate(0,K);
{
paint.setColor(SK_ColorBLACK);
canvas->drawString("Adjacent rects, wound opposite. All green?",
K*1.5f, K*0.5f, SkFont(), paint);
paint.setColor(SK_ColorRED);
canvas->drawRect({0,0,K,K}, paint);
{
SkPath path = SkPathBuilder().addPolygon({{0,0},{0,K},{K*0.5f,K},{K*0.5f,0}}, false)
.addPolygon({{K*0.5f,0},{K,0},{K,K},{K*0.5f,K}}, false)
.detach();
paint.setColor(SK_ColorGREEN);
canvas->drawPath(path, paint);
}
}
canvas->translate(0,K);
{
paint.setColor(SK_ColorBLACK);
canvas->drawString("One poly, wound opposite. All green?",
K*1.5f, K*0.5f, SkFont(), paint);
paint.setColor(SK_ColorRED);
canvas->drawRect({0,0,K,K}, paint);
SkPath path = SkPath::Polygon({{K*0.5f,0},{0,0},{0,K},{K*0.5f,K},
{K*0.5f,0},{K,0},{K,K},{K*0.5f,K}},
false);
paint.setColor(SK_ColorGREEN);
canvas->drawPath(path, paint);
}
}