skia2/gm/mipmap.cpp
Cary Clark 2a475eae62 add drawString helper to canvas
Many tests and examples use drawText with
a guess of how long the text is in bytes,
or a call to strlen(). Add a helper to
SkCanvas to simplify these examples.

Add another helper for SkString.

R=reed@google.com

Change-Id: I0204a31e938f065606f08ee7cd9a6b36db791ee2
Reviewed-on: https://skia-review.googlesource.com/13642
Commit-Queue: Cary Clark <caryclark@google.com>
Reviewed-by: Cary Clark <caryclark@google.com>
Reviewed-by: Mike Reed <reed@google.com>
Reviewed-by: Cary Clark <caryclark@skia.org>
2017-04-28 20:41:04 +00:00

149 lines
4.9 KiB
C++

/*
* Copyright 2015 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "gm.h"
#include "sk_tool_utils.h"
#include "SkCanvas.h"
#include "SkImage.h"
#include "SkRandom.h"
#include "SkSurface.h"
static sk_sp<SkImage> make_image() {
const SkImageInfo info = SkImageInfo::MakeN32Premul(319, 52);
auto surface(SkSurface::MakeRaster(info));
SkCanvas* canvas = surface->getCanvas();
canvas->drawColor(sk_tool_utils::color_to_565(0xFFF8F8F8));
SkPaint paint;
paint.setAntiAlias(true);
paint.setStyle(SkPaint::kStroke_Style);
for (int i = 0; i < 20; ++i) {
canvas->drawCircle(-4, 25, 20, paint);
canvas->translate(25, 0);
}
return surface->makeImageSnapshot();
}
DEF_SIMPLE_GM(mipmap, canvas, 400, 200) {
sk_sp<SkImage> img(make_image());//SkImage::NewFromEncoded(data));
SkPaint paint;
const SkRect dst = SkRect::MakeWH(177, 15);
paint.setTextSize(30);
SkString str;
str.printf("scale %g %g", dst.width() / img->width(), dst.height() / img->height());
// canvas->drawString(str, 300, 100, paint);
canvas->translate(20, 20);
for (int i = 0; i < 4; ++i) {
paint.setFilterQuality(SkFilterQuality(i));
canvas->drawImageRect(img.get(), dst, &paint);
canvas->translate(0, 20);
}
canvas->drawImage(img.get(), 20, 20, nullptr);
}
///////////////////////////////////////////////////////////////////////////////////////////////////
// create a circle image computed raw, so we can wrap it as a linear or srgb image
static sk_sp<SkImage> make(sk_sp<SkColorSpace> cs) {
const int N = 100;
SkImageInfo info = SkImageInfo::Make(N, N, kN32_SkColorType, kPremul_SkAlphaType, cs);
SkBitmap bm;
bm.allocPixels(info);
for (int y = 0; y < N; ++y) {
for (int x = 0; x < N; ++x) {
*bm.getAddr32(x, y) = (x ^ y) & 1 ? 0xFFFFFFFF : 0xFF000000;
}
}
bm.setImmutable();
return SkImage::MakeFromBitmap(bm);
}
static void show_mips(SkCanvas* canvas, SkImage* img) {
SkPaint paint;
paint.setFilterQuality(kMedium_SkFilterQuality);
// Want to ensure we never draw fractional pixels, so we use an IRect
SkIRect dst = SkIRect::MakeWH(img->width(), img->height());
while (dst.width() > 5) {
canvas->drawImageRect(img, SkRect::Make(dst), &paint);
dst.offset(dst.width() + 10, 0);
dst.fRight = dst.fLeft + dst.width()/2;
dst.fBottom = dst.fTop + dst.height()/2;
}
}
/*
* Ensure that in L32 drawing mode, both images/mips look the same as each other, and
* their mips are darker than the original (since the mips should ignore the gamma in L32).
*
* Ensure that in S32 drawing mode, all images/mips look the same, and look correct (i.e.
* the mip levels match the original in brightness).
*/
DEF_SIMPLE_GM(mipmap_srgb, canvas, 260, 230) {
sk_sp<SkImage> limg = make(nullptr);
sk_sp<SkImage> simg = make(SkColorSpace::MakeSRGB());
canvas->translate(10, 10);
show_mips(canvas, limg.get());
canvas->translate(0, limg->height() + 10.0f);
show_mips(canvas, simg.get());
}
///////////////////////////////////////////////////////////////////////////////////////////////////
// create a gradient image computed raw, so we can wrap it as a linear or srgb image
static sk_sp<SkImage> make_g8_gradient(sk_sp<SkColorSpace> cs) {
const int N = 100;
SkImageInfo info = SkImageInfo::Make(N, N, kGray_8_SkColorType, kOpaque_SkAlphaType, cs);
SkBitmap bm;
bm.allocPixels(info);
for (int y = 0; y < N; ++y) {
for (int x = 0; x < N; ++x) {
*bm.getAddr8(x, y) = static_cast<uint8_t>(255.0f * ((x + y) / (2.0f * (N - 1))));
}
}
bm.setImmutable();
return SkImage::MakeFromBitmap(bm);
}
static void show_mips_only(SkCanvas* canvas, SkImage* img) {
SkPaint paint;
paint.setFilterQuality(kMedium_SkFilterQuality);
// Want to ensure we never draw fractional pixels, so we use an IRect
SkIRect dst = SkIRect::MakeWH(img->width() / 2, img->height() / 2);
while (dst.width() > 5) {
canvas->drawImageRect(img, SkRect::Make(dst), &paint);
dst.offset(dst.width() + 10, 0);
dst.fRight = dst.fLeft + dst.width() / 2;
dst.fBottom = dst.fTop + dst.height() / 2;
}
}
/*
* Ensure that in L32 drawing mode, both images/mips look the same as each other, and
* their mips are darker than the original (since the mips should ignore the gamma in L32).
*
* Ensure that in S32 drawing mode, all images/mips look the same, and look correct (i.e.
* the mip levels match the original in brightness).
*/
DEF_SIMPLE_GM(mipmap_gray8_srgb, canvas, 260, 230) {
sk_sp<SkImage> limg = make_g8_gradient(nullptr);
sk_sp<SkImage> simg = make_g8_gradient(SkColorSpace::MakeSRGB());
canvas->translate(10, 10);
show_mips_only(canvas, limg.get());
canvas->translate(0, limg->height() + 10.0f);
show_mips_only(canvas, simg.get());
}