...

9 files changed, 103 insertions, 5 deletions

diff --git a/include/cru/platform/graphics/web_canvas/WebCanvasPainter.h b/include/cru/platform/graphics/web_canvas/WebCanvasPainter.h
index cd885aa4..1f7d21b6 100644
--- a/include/cru/platform/graphics/web_canvas/WebCanvasPainter.h
+++ b/include/cru/platform/graphics/web_canvas/WebCanvasPainter.h
@@ -1,11 +1,20 @@
 #pragma once
 #include "../Painter.h"
+#include "WebCanvasRef.h"
 #include "WebCanvasResource.h"
 
 #include <emscripten/val.h>
 #include <optional>
 
 namespace cru::platform::graphics::web_canvas {
+/**
+ * Notes about Transform:
+ * Although there is a Matrix object now supported by browsers, it is not
+ * generally available in old browsers. However, now that we are using
+ * WebAssembly, the browsers should be quite up to date, but there is still a
+ * window between the two things. And it is common for a platform to not support
+ * getting transform and only allow you to do transformation.
+ */
 class WebCanvasPainter : public WebCanvasResource, public virtual IPainter {
  public:
   WebCanvasPainter(WebCanvasGraphicsFactory* factory, emscripten::val context,
@@ -17,6 +26,13 @@ class WebCanvasPainter : public WebCanvasResource, public virtual IPainter {
   Matrix GetTransform() override;
   void SetTransform(const Matrix& transform) override;
 
+  void ConcatTransform(const Matrix& matrix) override;
+
+  void Clear(const Color& color) override;
+
+  emscripten::val GetCanvas2DContext() const { return context_; }
+  WebCanvasRef GetCanvas();
+
  private:
   Matrix current_transform_;
   emscripten::val context_;
diff --git a/include/cru/platform/graphics/web_canvas/WebCanvasRef.h b/include/cru/platform/graphics/web_canvas/WebCanvasRef.h
new file mode 100644
index 00000000..4cb960bd
--- /dev/null
+++ b/include/cru/platform/graphics/web_canvas/WebCanvasRef.h
@@ -0,0 +1,24 @@
+#pragma once
+
+#include "cru/common/Base.h"
+
+#include <emscripten/val.h>
+
+namespace cru::platform::graphics::web_canvas {
+  class WebCanvasRef {
+    public:
+      explicit WebCanvasRef(emscripten::val canvas_val);
+
+      CRU_DEFAULT_COPY(WebCanvasRef)
+      CRU_DEFAULT_MOVE(WebCanvasRef)
+
+      CRU_DEFAULT_DESTRUCTOR(WebCanvasRef)
+
+    public:
+      int GetWidth() const;
+      int GetHeight() const;
+
+    private:
+      emscripten::val val_;
+  };
+}
diff --git a/include/cru/platform/web/JsUtility.h b/include/cru/platform/web/JsUtility.h
new file mode 100644
index 00000000..37c2735d
--- /dev/null
+++ b/include/cru/platform/web/JsUtility.h
@@ -0,0 +1,9 @@
+#pragma once
+
+#include <emscripten/val.h>
+
+namespace cru::platform::web {
+  bool IsNotNullAndInstanceOf(const emscripten::val& value, const emscripten::val& type);
+  bool IsNotNullAndInstanceOf(const emscripten::val& value, const char* global_type);
+}
+
diff --git a/src/platform/graphics/web_canvas/CMakeLists.txt b/src/platform/graphics/web_canvas/CMakeLists.txt
index 6edc2edb..bbf736e0 100644
--- a/src/platform/graphics/web_canvas/CMakeLists.txt
+++ b/src/platform/graphics/web_canvas/CMakeLists.txt
@@ -3,6 +3,7 @@ add_library(CruPlatformGraphicsWebCanvas
 	Factory.cpp
 	Painter.cpp
 	Resource.cpp
+	WebCanvasRef.cpp
 )
 
 target_link_libraries(CruPlatformGraphicsWebCanvas PUBLIC CruPlatformBaseWeb CruPlatformGraphics)
diff --git a/src/platform/graphics/web_canvas/Factory.cpp b/src/platform/graphics/web_canvas/Factory.cpp
index e69de29b..be14ae18 100644
--- a/src/platform/graphics/web_canvas/Factory.cpp
+++ b/src/platform/graphics/web_canvas/Factory.cpp
@@ -0,0 +1,7 @@
+#include "cru/platform/graphics/web_canvas/WebCanvasGraphicsFactory.h"
+
+namespace cru::platform::graphics::web_canvas {
+WebCanvasGraphicsFactory::WebCanvasGraphicsFactory() { }
+
+WebCanvasGraphicsFactory::~WebCanvasGraphicsFactory() { }
+}
diff --git a/src/platform/graphics/web_canvas/Painter.cpp b/src/platform/graphics/web_canvas/Painter.cpp
index cd04a725..31c4a53d 100644
--- a/src/platform/graphics/web_canvas/Painter.cpp
+++ b/src/platform/graphics/web_canvas/Painter.cpp
@@ -1,5 +1,6 @@
 #include "cru/platform/graphics/web_canvas/WebCanvasGraphicsFactory.h"
 #include "cru/platform/graphics/web_canvas/WebCanvasPainter.h"
+#include "cru/platform/graphics/web_canvas/WebCanvasRef.h"
 #include "cru/platform/graphics/web_canvas/WebCanvasResource.h"
 
 #include <optional>
@@ -7,9 +8,10 @@
 namespace cru::platform::graphics::web_canvas {
 
 namespace {
-void contextSetTransform(emscripten::val context, const Matrix& matrix) {
-  context.call<void>("setTransform", matrix.m11, matrix.m12, matrix.m21,
-                     matrix.m22, matrix.m31, matrix.m32);
+void contextDoTransform(emscripten::val context, const char* method,
+                        const Matrix& matrix) {
+  context.call<void>(method, matrix.m11, matrix.m12, matrix.m21, matrix.m22,
+                     matrix.m31, matrix.m32);
 }
 }  // namespace
 
@@ -19,7 +21,7 @@ WebCanvasPainter::WebCanvasPainter(WebCanvasGraphicsFactory* factory,
     : WebCanvasResource(factory),
       context_(context),
       current_transform_(current_transform.value_or(Matrix::Identity())) {
-  contextSetTransform(context_, current_transform_);
+  contextDoTransform(context_, "setTransform", current_transform_);
 }
 
 WebCanvasPainter::~WebCanvasPainter() {}
@@ -28,6 +30,17 @@ Matrix WebCanvasPainter::GetTransform() { return current_transform_; }
 
 void WebCanvasPainter::SetTransform(const Matrix& transform) {
   current_transform_ = transform;
-  contextSetTransform(context_, transform);
+  contextDoTransform(context_, "setTransform", current_transform_);
+}
+
+void WebCanvasPainter::ConcatTransform(const Matrix& transform) {
+  current_transform_ *= transform;
+  contextDoTransform(context_, "transform", transform);
+}
+
+void WebCanvasPainter::Clear(const Color& color) {}
+
+WebCanvasRef WebCanvasPainter::GetCanvas() {
+  return WebCanvasRef(context_["canvas"]);
 }
 }  // namespace cru::platform::graphics::web_canvas
diff --git a/src/platform/graphics/web_canvas/WebCanvasRef.cpp b/src/platform/graphics/web_canvas/WebCanvasRef.cpp
new file mode 100644
index 00000000..c4f75626
--- /dev/null
+++ b/src/platform/graphics/web_canvas/WebCanvasRef.cpp
@@ -0,0 +1,16 @@
+#include "cru/platform/graphics/web_canvas/WebCanvasRef.h"
+#include "cru/platform/web/JsUtility.h"
+
+#include <cassert>
+#include <utility>
+
+namespace cru::platform::graphics::web_canvas {
+WebCanvasRef::WebCanvasRef(emscripten::val canvas_val)
+    : val_(std::move(canvas_val)) {
+  assert(web::IsNotNullAndInstanceOf(val_, "HTMLCanvasElement"));
+}
+
+int WebCanvasRef::GetWidth() const { return val_["width"].as<int>(); }
+
+int WebCanvasRef::GetHeight() const { return val_["height"].as<int>(); }
+}  // namespace cru::platform::graphics::web_canvas
diff --git a/src/platform/web/CMakeLists.txt b/src/platform/web/CMakeLists.txt
index 1287f85a..0a9bd6dd 100644
--- a/src/platform/web/CMakeLists.txt
+++ b/src/platform/web/CMakeLists.txt
@@ -1,4 +1,5 @@
 add_library(CruPlatformBaseWeb
+	JsUtility.cpp
 	Resource.cpp
 )
 
diff --git a/src/platform/web/JsUtility.cpp b/src/platform/web/JsUtility.cpp
new file mode 100644
index 00000000..b426bbda
--- /dev/null
+++ b/src/platform/web/JsUtility.cpp
@@ -0,0 +1,11 @@
+#include "cru/platform/web/JsUtility.h"
+
+namespace cru::platform::web {
+bool IsNotNullAndInstanceOf(const emscripten::val& value, const emscripten::val& type) {
+  return !value.isNull() && !type.isNull() && value.instanceof(type);
+}
+
+bool IsNotNullAndInstanceOf(const emscripten::val& value, const char* global_type) {
+  return IsNotNullAndInstanceOf(value, emscripten::val::global(global_type));
+}
+}