From 97119e5b3c1e5b8636e8160af4f782a5387e1a17 Mon Sep 17 00:00:00 2001
From: John Stiles <johnstiles@google.com>
Date: Wed, 8 Dec 2021 10:34:52 -0500
Subject: [PATCH] Add "Write Debug Trace/Dump" buttons to SkSL slide in Viewer.

Click these buttons to trace execution of the current SkSL program.
This demonstrates end-to-end debug trace functionality in
SkRuntimeEffect.

Change-Id: I684099e337d1d275e444eb33dfa3a9e99343bb17
Bug: skia:12708
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/481336
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
---
 tools/viewer/SkSLSlide.cpp | 28 +++++++++++++++++++++++++++-
 tools/viewer/SkSLSlide.h   |  1 +
 2 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/tools/viewer/SkSLSlide.cpp b/tools/viewer/SkSLSlide.cpp
index 96583450db..cfe14fb19a 100644
--- a/tools/viewer/SkSLSlide.cpp
+++ b/tools/viewer/SkSLSlide.cpp
@@ -11,6 +11,7 @@
 #include "include/core/SkFont.h"
 #include "include/effects/SkGradientShader.h"
 #include "include/effects/SkPerlinNoiseShader.h"
+#include "include/sksl/SkSLDebugTrace.h"
 #include "src/core/SkEnumerate.h"
 #include "tools/Resources.h"
 #include "tools/viewer/Viewer.h"
@@ -140,6 +141,14 @@ void SkSLSlide::draw(SkCanvas* canvas) {
         return;
     }
 
+    bool writeTrace = false;
+    bool writeDump = false;
+    if (!canvas->recordingContext()) {
+        ImGui::InputInt2("Trace Coordinate (X/Y)", fTraceCoord);
+        writeTrace = ImGui::Button("Write Debug Trace (JSON)");
+        writeDump = ImGui::Button("Write Debug Dump (Human-Readable)");
+    }
+
     // Update fMousePos
     ImVec2 mousePos = ImGui::GetMousePos();
     if (ImGui::IsMouseDown(0)) {
@@ -246,9 +255,17 @@ void SkSLSlide::draw(SkCanvas* canvas) {
     ImGui::End();
 
     auto inputs = SkData::MakeWithoutCopy(fInputs.get(), fEffect->uniformSize());
+
+    sk_sp<SkSL::DebugTrace> debugTrace;
     auto shader = fEffect->makeShader(std::move(inputs), fChildren.data(), fChildren.count(),
                                       nullptr, false);
-
+    if (writeTrace || writeDump) {
+        SkIPoint traceCoord = {fTraceCoord[0], fTraceCoord[1]};
+        SkRuntimeEffect::TracedShader traced = SkRuntimeEffect::MakeTraced(std::move(shader),
+                                                                           traceCoord);
+        shader = std::move(traced.shader);
+        debugTrace = std::move(traced.debugTrace);
+    }
     SkPaint p;
     p.setColor4f(gPaintColor);
     p.setShader(std::move(shader));
@@ -274,6 +291,15 @@ void SkSLSlide::draw(SkCanvas* canvas) {
         } break;
         default: break;
     }
+
+    if (debugTrace && writeTrace) {
+        SkFILEWStream traceFile("SkVMDebugTrace.json");
+        debugTrace->writeTrace(&traceFile);
+    }
+    if (debugTrace && writeDump) {
+        SkFILEWStream dumpFile("SkVMDebugTrace.dump.txt");
+        debugTrace->dump(&dumpFile);
+    }
 }
 
 bool SkSLSlide::animate(double nanos) {
diff --git a/tools/viewer/SkSLSlide.h b/tools/viewer/SkSLSlide.h
index 75810952a7..bb6cdc5a45 100644
--- a/tools/viewer/SkSLSlide.h
+++ b/tools/viewer/SkSLSlide.h
@@ -51,6 +51,7 @@ private:
     int fGeometry = kFill;
     SkV3 fResolution = { 1, 1, 1 };
     SkV4 fMousePos;
+    int fTraceCoord[2] = {64, 64};
 
     // Named shaders that can be selected as inputs
     SkTArray<std::pair<const char*, sk_sp<SkShader>>> fShaders;