Modify skia serve to return clip rect and view matrix

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1662003002

Review URL: https://codereview.chromium.org/1662003002

tools/json/SkJSONCanvas.cpp

@@ -382,7 +382,16 @@ Json::Value SkJSONCanvas::makePaint(const SkPaint& paint) {
     return result;
 }
 
-Json::Value SkJSONCanvas::makeMatrix(const SkMatrix& matrix) {
+Json::Value SkJSONCanvas::MakeIRect(const SkIRect& rect) {
+    Json::Value result(Json::arrayValue);
+    result.append(Json::Value(rect.left()));
+    result.append(Json::Value(rect.top()));
+    result.append(Json::Value(rect.right()));
+    result.append(Json::Value(rect.bottom()));
+    return result;
+}
+
+Json::Value SkJSONCanvas::MakeMatrix(const SkMatrix& matrix) {
     Json::Value result(Json::arrayValue);
     Json::Value row1(Json::arrayValue);
     row1.append(Json::Value(matrix[0]));
@@ -441,7 +450,7 @@ void SkJSONCanvas::updateMatrix() {
     if (matrix != fLastMatrix) {
         Json::Value command(Json::objectValue);
         command[SKJSONCANVAS_COMMAND] = Json::Value(SKJSONCANVAS_COMMAND_MATRIX);
-        command[SKJSONCANVAS_ATTRIBUTE_MATRIX] = this->makeMatrix(matrix);
+        command[SKJSONCANVAS_ATTRIBUTE_MATRIX] = MakeMatrix(matrix);
         fCommands.append(command);
         fLastMatrix = matrix;
     }

tools/json/SkJSONCanvas.h

@@ -149,6 +149,10 @@ public:
     /* Complete the JSON document. */
     void finish();
 
+    static Json::Value MakeMatrix(const SkMatrix& matrix);
+
+    static Json::Value MakeIRect(const SkIRect& irect);
+
     // overridden SkCanvas API
 
     void onDrawPaint(const SkPaint&) override;
@@ -226,6 +230,7 @@ public:
     SkCanvas::SaveLayerStrategy getSaveLayerStrategy(const SaveLayerRec& rec) override;
 
 private:
+    // Helpers to turn values into JSON, these could probably be static
     Json::Value makePoint(const SkPoint& point);
 
     Json::Value makePoint(SkScalar x, SkScalar y);
@@ -245,9 +250,7 @@ private:
     Json::Value makeEdgeStyle(SkCanvas::ClipEdgeStyle edgeStyle);
   
     Json::Value makePointMode(SkCanvas::PointMode mode);
-  
-    Json::Value makeMatrix(const SkMatrix& matrix);
-  
+
     void updateMatrix();
 
     SkWStream&  fOut;

tools/skiaserve/skiaserve.cpp

@@ -11,6 +11,7 @@
 #include "SkCommandLineFlags.h"
 #include "SkDebugCanvas.h"
 #include "SkJSONCanvas.h"
+#include "SkJSONCPP.h"
 #include "SkPicture.h"
 #include "SkPictureRecorder.h"
 #include "SkPixelSerializer.h"
@@ -117,6 +118,12 @@ SkData* setupAndDrawToCanvasReturnPng(SkDebugCanvas* debugCanvas, int n) {
     return writeCanvasToPng(canvas);
 }
 
+SkSurface* setupCpuSurface() {
+    SkImageInfo info = SkImageInfo::Make(kImageWidth, kImageHeight, kN32_SkColorType,
+                                         kPremul_SkAlphaType);
+    return SkSurface::NewRaster(info);
+}
+
 static const size_t kBufferSize = 1024;
 
 static int process_upload_data(void* cls, enum MHD_ValueKind kind,
@@ -188,7 +195,7 @@ public:
                        const char* upload_data, size_t* upload_data_size) = 0;
 };
 
-class InfoHandler : public UrlHandler {
+class CmdHandler : public UrlHandler {
 public:
     bool canHandle(const char* method, const char* url) override {
         const char* kBasePath = "/cmd";
@@ -356,6 +363,55 @@ public:
     }
 };
 
+class InfoHandler : public UrlHandler {
+public:
+    bool canHandle(const char* method, const char* url) override {
+        const char* kBaseName = "/info";
+        return 0 == strcmp(method, MHD_HTTP_METHOD_GET) &&
+               0 == strncmp(url, kBaseName, strlen(kBaseName));
+    }
+
+    int handle(Request* request, MHD_Connection* connection,
+               const char* url, const char* method,
+               const char* upload_data, size_t* upload_data_size) override {
+        SkTArray<SkString> commands;
+        SkStrSplit(url, "/", &commands);
+
+        if (!request->fPicture.get() || commands.count() > 2) {
+            return MHD_NO;
+        }
+
+        // drawTo
+        SkAutoTUnref<SkSurface> surface(setupCpuSurface());
+        SkCanvas* canvas = surface->getCanvas();
+
+        int n;
+        // /info or /info/N
+        if (commands.count() == 1) {
+            n = request->fDebugCanvas->getSize() - 1;
+        } else {
+            sscanf(commands[1].c_str(), "%d", &n);
+        }
+
+        // TODO this is really slow and we should cache the matrix and clip
+        request->fDebugCanvas->drawTo(canvas, n);
+
+        // make some json
+        SkMatrix vm = request->fDebugCanvas->getCurrentMatrix();
+        SkIRect clip = request->fDebugCanvas->getCurrentClip();
+        Json::Value info(Json::objectValue);
+        info["ViewMatrix"] = SkJSONCanvas::MakeMatrix(vm);
+        info["ClipRect"] = SkJSONCanvas::MakeIRect(clip);
+
+        std::string json = Json::FastWriter().write(info);
+
+        // We don't want the null terminator so strlen is correct
+        SkAutoTUnref<SkData> data(SkData::NewWithCopy(json.c_str(), strlen(json.c_str())));
+        return SendData(connection, data, "application/json");
+    }
+};
+
+
 class RootHandler : public UrlHandler {
 public:
     bool canHandle(const char* method, const char* url) override {
@@ -377,6 +433,7 @@ public:
         fHandlers.push_back(new RootHandler);
         fHandlers.push_back(new PostHandler);
         fHandlers.push_back(new ImgHandler);
+        fHandlers.push_back(new CmdHandler);
         fHandlers.push_back(new InfoHandler);
         fHandlers.push_back(new DownloadHandler);
     }