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/*
* 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.h"
#include "Sk3D.h"
#include "SkPath.h"
#include "SkPoint3.h"
class GM3d : public skiagm::GM {
float fNear = 0.5;
float fFar = 4;
float fAngle = SK_ScalarPI / 4;
SkPoint3 fEye { 0, 0, 4 };
SkPoint3 fCOA {0,0,0};//{ 0.5f, 0.5f, 0.5f };
SkPoint3 fUp { 0, 1, 0 };
SkMatrix44 fMV;
SkPoint3 fP3[8];
public:
GM3d() : fMV(SkMatrix44::kIdentity_Constructor) {}
~GM3d() override {}
protected:
void onOnceBeforeDraw() override {
int index = 0;
for (float x = 0; x <= 1; ++x) {
for (float y = 0; y <= 1; ++y) {
for (float z = 0; z <= 1; ++z) {
fP3[index++] = { x, y, z };
}
}
}
fMV.setIdentity();
}
static void draw_viewport(SkCanvas* canvas, const SkMatrix& viewport) {
SkPaint p;
p.setColor(0x10FF0000);
canvas->save();
canvas->concat(viewport);
canvas->drawRect({-1, -1, 1, 1}, p);
p.setColor(0x80FF0000);
canvas->drawLine({-1, -1}, {1, 1}, p);
canvas->drawLine({1, -1}, {-1, 1}, p);
canvas->restore();
}
void onDraw(SkCanvas* canvas) override {
SkMatrix44 camera(SkMatrix44::kIdentity_Constructor),
perspective(SkMatrix44::kIdentity_Constructor),
mv = fMV;
SkMatrix viewport;
{
float w = this->width();
float h = this->height();
float s = std::min(w, h);
viewport.setTranslate(1, -1);
viewport.postScale(s/2, -s/2);
draw_viewport(canvas, viewport);
}
Sk3Perspective(&perspective, fNear, fFar, fAngle);
Sk3LookAt(&camera, fEye, fCOA, fUp);
mv.postConcat(camera);
mv.postConcat(perspective);
SkPoint pts[8];
Sk3MapPts(pts, mv, fP3, 8);
viewport.mapPoints(pts, 8);
SkPaint paint;
paint.setStyle(SkPaint::kStroke_Style);
SkPath cube;
cube.moveTo(pts[0]);
cube.lineTo(pts[2]);
cube.lineTo(pts[6]);
cube.lineTo(pts[4]);
cube.close();
cube.moveTo(pts[1]);
cube.lineTo(pts[3]);
cube.lineTo(pts[7]);
cube.lineTo(pts[5]);
cube.close();
cube.moveTo(pts[0]); cube.lineTo(pts[1]);
cube.moveTo(pts[2]); cube.lineTo(pts[3]);
cube.moveTo(pts[4]); cube.lineTo(pts[5]);
cube.moveTo(pts[6]); cube.lineTo(pts[7]);
canvas->drawPath(cube, paint);
{
SkPoint3 src[4] = {
{ 0, 0, 0 }, { 2, 0, 0 }, { 0, 2, 0 }, { 0, 0, 2 },
};
SkPoint dst[4];
mv.setConcat(perspective, camera);
Sk3MapPts(dst, mv, src, 4);
viewport.mapPoints(dst, 4);
const char str[] = "XYZ";
for (int i = 1; i <= 3; ++i) {
canvas->drawLine(dst[0], dst[i], paint);
}
for (int i = 1; i <= 3; ++i) {
canvas->drawText(&str[i-1], 1, dst[i].fX, dst[i].fY, paint);
}
}
}
SkISize onISize() override { return { 1024, 768 }; }
SkString onShortName() override { return SkString("3dgm"); }
bool onAnimate(const SkAnimTimer&) override { return false; }
bool onHandleKey(SkUnichar uni) override {
switch (uni) {
case 'a': fEye.fX += 0.125f; return true;
case 'd': fEye.fX -= 0.125f; return true;
case 'w': fEye.fY += 0.125f; return true;
case 's': fEye.fY -= 0.125f; return true;
case 'q': fEye.fZ += 0.125f; return true;
case 'z': fEye.fZ -= 0.125f; return true;
default: break;
}
return false;
}
bool onGetControls(SkMetaData*) override { return false; }
void onSetControls(const SkMetaData&) override {
}
};
DEF_GM(return new GM3d;)
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