More cleanup in the Vulkan viewer

* add animation support for GMs
* don't load all SkPictures at start, only as needed
* don't update constantly, only for animation or stats
* hide/show stats
* scale slides up/down

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1873733003

Review URL: https://codereview.chromium.org/1873733003

13 files changed, 223 insertions, 81 deletions

diff --git a/gm/scaledstrokes.cpp b/gm/scaledstrokes.cpp
index 59c3efb1cc..1ee2350236 100644
--- a/gm/scaledstrokes.cpp
+++ b/gm/scaledstrokes.cpp
@@ -73,6 +73,7 @@ protected:
 
                 canvas->translate(80.0f, 0.0f);
             }
+            canvas->restore();
         }
 
     }
diff --git a/tools/vulkan/Window.cpp b/tools/vulkan/Window.cpp
index 2741f4da4c..9042a0cb69 100644
--- a/tools/vulkan/Window.cpp
+++ b/tools/vulkan/Window.cpp
@@ -67,7 +67,8 @@ void Window::onPaint() {
 
 }
 
-
 void Window::onResize(uint32_t w, uint32_t h) {
+    fWidth = w;
+    fHeight = h;
     fTestContext->resize(w, h);
 }
diff --git a/tools/vulkan/Window.h b/tools/vulkan/Window.h
index f7b4f132ad..c8971eebbe 100644
--- a/tools/vulkan/Window.h
+++ b/tools/vulkan/Window.h
@@ -21,6 +21,7 @@ public:
 
     virtual void setTitle(const char*) = 0;
     virtual void show() = 0;
+    virtual void inval() = 0;
 
     struct AttachmentInfo {
         int fSampleCount;
@@ -122,9 +123,15 @@ public:
     void onPaint();
     void onResize(uint32_t width, uint32_t height);
 
+    uint32_t width() { return fWidth; }
+    uint32_t height() { return fHeight;  }
+
 protected:
     Window();
 
+    uint32_t     fWidth;
+    uint32_t     fHeight;
+
     OnCharFunc   fCharFunc;
     void*        fCharUserData;
     OnKeyFunc    fKeyFunc;
diff --git a/tools/vulkan/viewer/GMSlide.cpp b/tools/vulkan/viewer/GMSlide.cpp
index 59a00cfcbe..6096044a38 100644
--- a/tools/vulkan/viewer/GMSlide.cpp
+++ b/tools/vulkan/viewer/GMSlide.cpp
@@ -26,3 +26,7 @@ void GMSlide::draw(SkCanvas* canvas) {
     fGM->drawBackground(canvas);
     fGM->drawContent(canvas);
 }
+
+bool GMSlide::animate(const SkAnimTimer& timer) {
+    return fGM->animate(timer);
+}
diff --git a/tools/vulkan/viewer/GMSlide.h b/tools/vulkan/viewer/GMSlide.h
index e827287c66..c9ed0844ea 100644
--- a/tools/vulkan/viewer/GMSlide.h
+++ b/tools/vulkan/viewer/GMSlide.h
@@ -17,6 +17,7 @@ public:
     ~GMSlide() override;
 
     void draw(SkCanvas* canvas) override;
+    bool animate(const SkAnimTimer&) override;
 
 private:
     skiagm::GM* fGM;
diff --git a/tools/vulkan/viewer/SKPSlide.cpp b/tools/vulkan/viewer/SKPSlide.cpp
index 72f68b5cb5..6a9899b92f 100644
--- a/tools/vulkan/viewer/SKPSlide.cpp
+++ b/tools/vulkan/viewer/SKPSlide.cpp
@@ -8,25 +8,51 @@
 #include "SKPSlide.h"
 
 #include "SkCanvas.h"
+#include "SkCommonFlags.h"
+#include "SkOSFile.h"
+#include "SkStream.h"
 
-SKPSlide::SKPSlide(const char* name, sk_sp<const SkPicture> pic)
-    : fPic(pic)
-    , fCullRect(fPic->cullRect().roundOut()) {
+SKPSlide::SKPSlide(const SkString& name, const SkString& path) : fPath(path) {
     fName = name;
 }
 
 SKPSlide::~SKPSlide() {}
 
 void SKPSlide::draw(SkCanvas* canvas) {
-    bool isOffset = SkToBool(fCullRect.left() | fCullRect.top());
-    if (isOffset) {
-        canvas->save();
-        canvas->translate(SkIntToScalar(-fCullRect.left()), SkIntToScalar(-fCullRect.top()));
+    if (fPic.get()) {
+        bool isOffset = SkToBool(fCullRect.left() | fCullRect.top());
+        if (isOffset) {
+            canvas->save();
+            canvas->translate(SkIntToScalar(-fCullRect.left()), SkIntToScalar(-fCullRect.top()));
+        }
+
+        canvas->drawPicture(fPic.get());
+
+        if (isOffset) {
+            canvas->restore();
+        }
     }
+}
 
-    canvas->drawPicture(fPic.get());
+static sk_sp<SkPicture> read_picture(const char path[]) {
+    SkAutoTDelete<SkStream> stream(SkStream::NewFromFile(path));
+    if (stream.get() == nullptr) {
+        SkDebugf("Could not read %s.\n", path);
+        return nullptr;
+    }
 
-    if (isOffset) {
-        canvas->restore();
+    auto pic = SkPicture::MakeFromStream(stream.get());
+    if (!pic) {
+        SkDebugf("Could not read %s as an SkPicture.\n", path);
     }
+    return pic;
+}
+
+void SKPSlide::load() {
+    fPic = read_picture(fPath.c_str());
+    fCullRect = fPic->cullRect().roundOut();
+}
+
+void SKPSlide::unload() {
+    fPic.reset(nullptr);
 }
diff --git a/tools/vulkan/viewer/SKPSlide.h b/tools/vulkan/viewer/SKPSlide.h
index 60be9d81e9..73fd5a1f3f 100644
--- a/tools/vulkan/viewer/SKPSlide.h
+++ b/tools/vulkan/viewer/SKPSlide.h
@@ -13,12 +13,15 @@
 
 class SKPSlide : public Slide {
 public:
-    SKPSlide(const char* name, sk_sp<const SkPicture> pic);
+    SKPSlide(const SkString& name, const SkString& path);
     ~SKPSlide() override;
 
     void draw(SkCanvas* canvas) override;
+    void load() override;
+    void unload() override;
 
 private:
+    SkString               fPath;
     sk_sp<const SkPicture> fPic;
     SkIRect                fCullRect;
 };
diff --git a/tools/vulkan/viewer/Slide.h b/tools/vulkan/viewer/Slide.h
index 742a345f95..f75e3fd6c5 100644
--- a/tools/vulkan/viewer/Slide.h
+++ b/tools/vulkan/viewer/Slide.h
@@ -12,12 +12,17 @@
 #include "SkString.h"
 
 class SkCanvas;
+class SkAnimTimer;
 
 class Slide : public SkRefCnt {
 public:
     virtual ~Slide() {}
 
     virtual void draw(SkCanvas* canvas) = 0;
+    virtual bool animate(const SkAnimTimer&) { return false;  }
+    virtual void load() {}
+    virtual void unload() {}
+
     SkString getName() { return fName; }
 
 protected:
diff --git a/tools/vulkan/viewer/VulkanViewer.cpp b/tools/vulkan/viewer/VulkanViewer.cpp
index 55da5546f7..52b6ad19f5 100644
--- a/tools/vulkan/viewer/VulkanViewer.cpp
+++ b/tools/vulkan/viewer/VulkanViewer.cpp
@@ -27,6 +27,12 @@ static bool on_key_handler(Window::Key key, Window::InputState state, uint32_t m
     return vv->onKey(key, state, modifiers);
 }
 
+static bool on_char_handler(SkUnichar c, uint32_t modifiers, void* userData) {
+    VulkanViewer* vv = reinterpret_cast<VulkanViewer*>(userData);
+
+    return vv->onChar(c, modifiers);
+}
+
 static void on_paint_handler(SkCanvas* canvas, void* userData) {
     VulkanViewer* vv = reinterpret_cast<VulkanViewer*>(userData);
 
@@ -46,12 +52,10 @@ DEFINE_string2(match, m, nullptr,
                "it is skipped unless some list entry starts with ~");
 DEFINE_string(skps, "skps", "Directory to read skps from.");
 
-
-
-
-
-
-VulkanViewer::VulkanViewer(int argc, char** argv, void* platformData) : fCurrentMeasurement(0) {
+VulkanViewer::VulkanViewer(int argc, char** argv, void* platformData)
+    : fCurrentMeasurement(0)
+    , fDisplayStats(false)
+{
     memset(fMeasurements, 0, sizeof(fMeasurements));
 
     SkDebugf("Command line arguments: ");
@@ -67,46 +71,18 @@ VulkanViewer::VulkanViewer(int argc, char** argv, void* platformData) : fCurrent
 
     // register callbacks
     fWindow->registerKeyFunc(on_key_handler, this);
+    fWindow->registerCharFunc(on_char_handler, this);
     fWindow->registerPaintFunc(on_paint_handler, this);
 
     // set up slides
     this->initSlides();
 
     // set up first frame
-    SkString title("VulkanViewer: ");
-    title.append(fSlides[0]->getName());
     fCurrentSlide = 0;
-    fWindow->setTitle(title.c_str());
-    fWindow->show();
-}
-
-static sk_sp<SkPicture> read_picture(const char path[]) {
-    if (SkCommandLineFlags::ShouldSkip(FLAGS_match, path)) {
-        return nullptr;
-    }
+    setupCurrentSlide(-1);
+    fLocalMatrix.reset();
 
-    SkAutoTDelete<SkStream> stream(SkStream::NewFromFile(path));
-    if (stream.get() == nullptr) {
-        SkDebugf("Could not read %s.\n", path);
-        return nullptr;
-    }
-
-    auto pic = SkPicture::MakeFromStream(stream.get());
-    if (!pic) {
-        SkDebugf("Could not read %s as an SkPicture.\n", path);
-    }
-    return pic;
-}
-
-
-static sk_sp<SKPSlide> loadSKP(const SkString& path) {
-    sk_sp<SkPicture> pic = read_picture(path.c_str());
-    if (!pic) {
-        return nullptr;
-    }
-
-    SkString name = SkOSPath::Basename(path.c_str());
-    return sk_sp<SKPSlide>(new SKPSlide(name.c_str(), pic));
+    fWindow->show();
 }
 
 void VulkanViewer::initSlides() {
@@ -132,17 +108,25 @@ void VulkanViewer::initSlides() {
     // SKPs
     for (int i = 0; i < FLAGS_skps.count(); i++) {
         if (SkStrEndsWith(FLAGS_skps[i], ".skp")) {
+            if (SkCommandLineFlags::ShouldSkip(FLAGS_match, FLAGS_skps[i])) {
+                continue;
+            }
+
             SkString path(FLAGS_skps[i]);
-            sk_sp<SKPSlide> slide = loadSKP(path);
+            sk_sp<SKPSlide> slide(new SKPSlide(SkOSPath::Basename(path.c_str()), path));
             if (slide) {
                 fSlides.push_back(slide);
             }
         } else {
             SkOSFile::Iter it(FLAGS_skps[i], ".skp");
-            SkString path;
-            while (it.next(&path)) {
-                SkString skpName = SkOSPath::Join(FLAGS_skps[i], path.c_str());
-                sk_sp<SKPSlide> slide = loadSKP(skpName);
+            SkString skpName;
+            while (it.next(&skpName)) {
+                if (SkCommandLineFlags::ShouldSkip(FLAGS_match, skpName.c_str())) {
+                    continue;
+                }
+
+                SkString path = SkOSPath::Join(FLAGS_skps[i], skpName.c_str());
+                sk_sp<SKPSlide> slide(new SKPSlide(skpName, path));
                 if (slide) {
                     fSlides.push_back(slide);
                 }
@@ -157,39 +141,124 @@ VulkanViewer::~VulkanViewer() {
     delete fWindow;
 }
 
+void VulkanViewer::setupCurrentSlide(int previousSlide) {
+    SkString title("VulkanViewer: ");
+    title.append(fSlides[fCurrentSlide]->getName());
+    fSlides[fCurrentSlide]->load();
+    if (previousSlide >= 0) {
+        fSlides[previousSlide]->unload();
+    }
+    fWindow->setTitle(title.c_str());
+    fWindow->inval();
+}
+
+#define MAX_ZOOM_LEVEL  8
+#define MIN_ZOOM_LEVEL  -8
+
+void VulkanViewer::changeZoomLevel(float delta) {
+    fZoomLevel += delta;
+    if (fZoomLevel > 0) {
+        fZoomLevel = SkMinScalar(fZoomLevel, MAX_ZOOM_LEVEL);
+        fZoomScale = fZoomLevel + SK_Scalar1;
+    } else if (fZoomLevel < 0) {
+        fZoomLevel = SkMaxScalar(fZoomLevel, MIN_ZOOM_LEVEL);
+        fZoomScale = SK_Scalar1 / (SK_Scalar1 - fZoomLevel);
+    } else {
+        fZoomScale = SK_Scalar1;
+    }
+    this->updateMatrix();
+}
+
+void VulkanViewer::updateMatrix(){
+    SkMatrix m;
+    m.reset();
+
+    if (fZoomLevel) {
+        SkPoint center;
+        //m = this->getLocalMatrix();//.invert(&m);
+        m.mapXY(fZoomCenterX, fZoomCenterY, &center);
+        SkScalar cx = center.fX;
+        SkScalar cy = center.fY;
+
+        m.setTranslate(-cx, -cy);
+        m.postScale(fZoomScale, fZoomScale);
+        m.postTranslate(cx, cy);
+    }
+
+    // TODO: add gesture support
+    // Apply any gesture matrix
+    //m.preConcat(fGesture.localM());
+    //m.preConcat(fGesture.globalM());
+
+    fLocalMatrix = m;
+}
+
 bool VulkanViewer::onKey(Window::Key key, Window::InputState state, uint32_t modifiers) {
-    if (Window::kDown_InputState == state && (modifiers & Window::kFirstPress_ModifierKey)) {
-        if (key == Window::kRight_Key) {
-            fCurrentSlide++;
-            if (fCurrentSlide >= fSlides.count()) {
-                fCurrentSlide = 0;
+    if (Window::kDown_InputState == state) {
+        switch (key) {
+            case Window::kRight_Key: {
+                int previousSlide = fCurrentSlide;
+                fCurrentSlide++;
+                if (fCurrentSlide >= fSlides.count()) {
+                    fCurrentSlide = 0;
+                }
+                setupCurrentSlide(previousSlide);
+                return true;
+            }
+
+            case Window::kLeft_Key: {
+                int previousSlide = fCurrentSlide;
+                fCurrentSlide--;
+                if (fCurrentSlide < 0) {
+                    fCurrentSlide = fSlides.count() - 1;
+                }
+                SkString title("VulkanViewer: ");
+                title.append(fSlides[fCurrentSlide]->getName());
+                fWindow->setTitle(title.c_str());
+                setupCurrentSlide(previousSlide);
+                return true;
+            }
+
+            case Window::kUp_Key: {
+                this->changeZoomLevel(1.f / 32.f);
+                return true;
             }
-            SkString title("VulkanViewer: ");
-            title.append(fSlides[fCurrentSlide]->getName());
-            fWindow->setTitle(title.c_str());
-        } else if (key == Window::kLeft_Key) {
-            fCurrentSlide--;
-            if (fCurrentSlide < 0) {
-                fCurrentSlide = fSlides.count()-1;
+
+            case Window::kDown_Key: {
+                this->changeZoomLevel(-1.f / 32.f);
+                return true;
             }
-            SkString title("VulkanViewer: ");
-            title.append(fSlides[fCurrentSlide]->getName());
-            fWindow->setTitle(title.c_str());
+
+            default:
+                break;
         }
     }
 
-    return true;
+    return false;
+}
+
+bool VulkanViewer::onChar(SkUnichar c, uint32_t modifiers) {
+    if ('s' == c) {
+        fDisplayStats = !fDisplayStats;
+        return true;
+    }
+
+    return false;
 }
 
 void VulkanViewer::onPaint(SkCanvas* canvas) {
 
     canvas->clear(SK_ColorWHITE);
 
-    canvas->save();
+    int count = canvas->save();
+    canvas->setMatrix(fLocalMatrix);
+
     fSlides[fCurrentSlide]->draw(canvas);
-    canvas->restore();
+    canvas->restoreToCount(count);
 
-    drawStats(canvas);
+    if (fDisplayStats) {
+        drawStats(canvas);
+    }
 }
 
 void VulkanViewer::drawStats(SkCanvas* canvas) {
@@ -240,5 +309,8 @@ void VulkanViewer::onIdle(double ms) {
     fCurrentMeasurement &= (kMeasurementCount - 1);  // fast mod
     SkASSERT(fCurrentMeasurement < kMeasurementCount);
 
-    fWindow->onPaint();
+    fAnimTimer.updateTime();
+    if (fDisplayStats || fSlides[fCurrentSlide]->animate(fAnimTimer)) {
+        fWindow->inval();
+    }
 }
diff --git a/tools/vulkan/viewer/VulkanViewer.h b/tools/vulkan/viewer/VulkanViewer.h
index 649cb22a53..7e39f88a76 100644
--- a/tools/vulkan/viewer/VulkanViewer.h
+++ b/tools/vulkan/viewer/VulkanViewer.h
@@ -11,6 +11,7 @@
 #include "../Application.h"
 #include "../Window.h"
 #include "gm.h"
+#include "SkAnimTimer.h"
 #include "Slide.h"
 
 class SkCanvas;
@@ -21,23 +22,38 @@ public:
     ~VulkanViewer() override;
 
     bool onKey(Window::Key key, Window::InputState state, uint32_t modifiers);
+    bool onChar(SkUnichar, uint32_t modifiers);
     void onPaint(SkCanvas* canvas);
-
     void onIdle(double ms) override;
 
 private:
     void initSlides();
+    void setupCurrentSlide(int previousSlide);
 
     void drawStats(SkCanvas* canvas);
 
+    void changeZoomLevel(float delta);
+    void updateMatrix();
+
     Window*      fWindow;
 
     static const int kMeasurementCount = 64;  // should be power of 2 for fast mod
     double fMeasurements[kMeasurementCount];
     int fCurrentMeasurement;
 
+    SkAnimTimer            fAnimTimer;
     SkTArray<sk_sp<Slide>> fSlides;
     int                    fCurrentSlide;
+
+    bool                   fDisplayStats;
+
+    // transform data
+    SkMatrix               fLocalMatrix;
+    SkScalar               fZoomCenterX;
+    SkScalar               fZoomCenterY;
+    SkScalar               fZoomLevel;
+    SkScalar               fZoomScale;
+
 };
 
 
diff --git a/tools/vulkan/win/Window_win.cpp b/tools/vulkan/win/Window_win.cpp
index 06238393dd..34a8ad2fa8 100644
--- a/tools/vulkan/win/Window_win.cpp
+++ b/tools/vulkan/win/Window_win.cpp
@@ -275,3 +275,7 @@ bool Window_win::attach(BackEndType attachType, int msaaSampleCount, AttachmentI
 
     return (SkToBool(fTestContext));
 }
+
+void Window_win::inval() {
+    InvalidateRect(fHWnd, nullptr, false);
+}
diff --git a/tools/vulkan/win/Window_win.h b/tools/vulkan/win/Window_win.h
index 6b95b56d2c..0be695dab5 100644
--- a/tools/vulkan/win/Window_win.h
+++ b/tools/vulkan/win/Window_win.h
@@ -23,6 +23,8 @@ public:
 
     bool attach(BackEndType attachType, int msaaSampleCount, AttachmentInfo*) override;
 
+    void inval() override;
+
 private:
     HINSTANCE fHInstance;
     HWND      fHWnd;
diff --git a/tools/vulkan/win/main_win.cpp b/tools/vulkan/win/main_win.cpp
index 883b96df9b..c2ad6dabbf 100644
--- a/tools/vulkan/win/main_win.cpp
+++ b/tools/vulkan/win/main_win.cpp
@@ -72,11 +72,11 @@ static int main_common(HINSTANCE hInstance, int show, int argc, char**argv) {
         if (PeekMessage(&msg, nullptr, 0, 0, PM_REMOVE)) {
             TranslateMessage(&msg);
             DispatchMessage(&msg);
-        } 
-        
-        previousTime = currentTime;
-        currentTime = now_ms();
-        app->onIdle(currentTime - previousTime);
+        } else {
+            previousTime = currentTime;
+            currentTime = now_ms();
+            app->onIdle(currentTime - previousTime);
+        }
     }
 
     delete app;