Addition of display list rendering in WinRT library

The display list rendering is used when scaling within the current page to
enable quicker response.

5 files changed, 113 insertions, 24 deletions

diff --git a/winrt/mupdf_cpp/MainPage.xaml.cpp b/winrt/mupdf_cpp/MainPage.xaml.cpp
index a8dc1b3a..3c886339 100644
--- a/winrt/mupdf_cpp/MainPage.xaml.cpp
+++ b/winrt/mupdf_cpp/MainPage.xaml.cpp
@@ -429,10 +429,10 @@ void mupdf_cpp::MainPage::RenderThumbs()
 	cancellation_token_source cts;
 	auto token = cts.get_token();
 	m_ThumbCancel = cts;
+	auto ui = task_continuation_context::use_current();
 
 	this->m_ren_status = REN_THUMBS;
 	Vector<DocumentPage^>^ thumbnails = m_thumbnails;
-	auto ui = task_continuation_context::use_current();
 	auto task_thumb = create_task([spatial_info, num_pages, thumbnails, this, ui, token]()-> int
 	{
 		spatial_info_t spatial_info_local = spatial_info;
@@ -441,7 +441,7 @@ void mupdf_cpp::MainPage::RenderThumbs()
 		for (int k = 0; k < num_pages; k++)
 		{
 			Point ras_size = ComputePageSize(spatial_info_local, k);
-			auto task2 = create_task(mu_doc->RenderPageAsync(k, ras_size.X, ras_size.Y));
+			auto task2 = create_task(mu_doc->RenderPageAsync(k, ras_size.X, ras_size.Y, false));
 
 			task2.then([this, k, thumbnails, ras_size](InMemoryRandomAccessStream^ ras)
 			{
@@ -640,7 +640,7 @@ void mupdf_cpp::MainPage::InitialRender()
 			Point ras_size = ComputePageSize(spatial_info, k);
 
 			auto render_task =
-				create_task(mu_doc->RenderPageAsync(k, ras_size.X, ras_size.Y));
+				create_task(mu_doc->RenderPageAsync(k, ras_size.X, ras_size.Y, false));
 
 			render_task.then([this, k, ras_size] (InMemoryRandomAccessStream^ ras)
 			{
@@ -687,7 +687,7 @@ void mupdf_cpp::MainPage::RenderRange(int curr_page)
 			{
 				Point ras_size = ComputePageSize(spatial_info, k);
 				auto render_task =
-					create_task(mu_doc->RenderPageAsync(k, ras_size.X, ras_size.Y));
+					create_task(mu_doc->RenderPageAsync(k, ras_size.X, ras_size.Y, false));
 
 				render_task.then([this, k, ras_size] (InMemoryRandomAccessStream^ ras)
 				{
@@ -745,7 +745,7 @@ void mupdf_cpp::MainPage::Slider_ValueChanged(Platform::Object^ sender, Windows:
 			spatial_info_t spatial_info = InitSpatial(1);
 			Point ras_size = ComputePageSize(spatial_info, newValue);
 			auto render_task =
-				create_task(mu_doc->RenderPageAsync(newValue, ras_size.X, ras_size.Y));
+				create_task(mu_doc->RenderPageAsync(newValue, ras_size.X, ras_size.Y, false));
 
 			render_task.then([this, newValue, ras_size] (InMemoryRandomAccessStream^ ras)
 			{
@@ -1321,17 +1321,26 @@ void mupdf_cpp::MainPage::ScrollChanged(Platform::Object^ sender,
 	{
 		doc_page->Zoom = scrollviewer->ZoomFactor;
 		int page = m_currpage;
+
 		/* Render at new resolution */
 		spatial_info_t spatial_info = InitSpatial(doc_page->Zoom);
 		Point ras_size = ComputePageSize(spatial_info, page);
 
-		auto render_task =
-			create_task(mu_doc->RenderPageAsync(page, ras_size.X, ras_size.Y));
-
-		render_task.then([this, page, ras_size] (InMemoryRandomAccessStream^ ras)
+		/* Go ahead and create display list if we dont have one for this page */
+		auto ui = task_continuation_context::use_current();
+		auto display_task = create_task(mu_doc->CreateDisplayList(page));
+		display_task.then([this, page, ras_size, ui] (int code)
 		{
-			ReplaceImage(page, ras, ras_size);
-		}, task_continuation_context::use_current());
+			if (code == S_ISOK)
+			{
+				auto render_task =
+					create_task(mu_doc->RenderPageAsync(page, ras_size.X, ras_size.Y, true));
+				render_task.then([this, page, ras_size] (InMemoryRandomAccessStream^ ras)
+				{
+					ReplaceImage(page, ras, ras_size);
+				}, ui);
+			}
+		});
 	}
 }
 
diff --git a/winrt/mupdfwinrt/muctx.cpp b/winrt/mupdfwinrt/muctx.cpp
index 63f008cf..40849fb9 100644
--- a/winrt/mupdfwinrt/muctx.cpp
+++ b/winrt/mupdfwinrt/muctx.cpp
@@ -134,21 +134,23 @@ muctx::muctx(void)
 	this->mu_ctx = NULL;
 	this->mu_doc = NULL;
 	this->mu_outline = NULL;
+	this->mu_dlist = NULL;
+	this->dlist_pagenum = -1;
 }
 
 /* Destructor */
 muctx::~muctx(void)
 {
-	if (mu_outline != NULL)
-		fz_free_outline(mu_ctx, mu_outline);
-	if (mu_doc != NULL)
-		fz_close_document(mu_doc);
-	if (mu_ctx != NULL)
-		fz_free_context(mu_ctx);
+	fz_free_outline(mu_ctx, mu_outline);
+	fz_close_document(mu_doc);
+	fz_free_display_list(mu_ctx, mu_dlist);
+	fz_free_context(mu_ctx);
 
 	this->mu_ctx = NULL;
 	this->mu_doc = NULL;
 	this->mu_outline = NULL;
+	this->mu_dlist = NULL;
+	this->dlist_pagenum = -1;
 }
 
 /* Set up the stream access */
@@ -404,9 +406,52 @@ int muctx::GetLinks(int page_num, sh_vector_link links_vec)
 	return num_links;
 }
 
+status_t muctx::CreateDisplayList(int page_num)
+{
+	fz_context *ctx_clone = NULL;
+	fz_device *dev = NULL;
+	fz_page *page = NULL;
+
+	ctx_clone = fz_clone_context(mu_ctx);
+
+	fz_var(dev);
+	fz_var(page);
+	fz_try(ctx_clone)
+	{
+		page = fz_load_page(mu_doc, page_num);
+
+		/* Free current list if we have one */
+		if (mu_dlist != NULL)
+			fz_free_display_list(ctx_clone, mu_dlist);
+
+		/* Create a new list */
+		mu_dlist = fz_new_display_list(ctx_clone);
+		dev = fz_new_list_device(ctx_clone, mu_dlist);
+		fz_run_page_contents(mu_doc, page, dev, &fz_identity, NULL);
+	}
+	fz_always(ctx_clone)
+	{
+		fz_free_device(dev);
+		fz_free_page(mu_doc, page);
+	}
+	fz_catch(ctx_clone)
+	{
+		fz_free_context(ctx_clone);
+		dlist_pagenum = -1;
+		return E_FAILURE;
+	}
+	dlist_pagenum = page_num;
+	return S_ISOK;
+}
+
+int muctx::GetDisplayListPage(void)
+{
+	return dlist_pagenum;
+}
+
 /* Render page_num to size width by height into bmp_data buffer */
 status_t muctx::RenderPage(int page_num, int width, int height,
-			  unsigned char *bmp_data)
+			unsigned char *bmp_data, bool use_dlist)
 {
 	fz_device *dev = NULL;
 	fz_pixmap *pix = NULL;
@@ -415,6 +460,9 @@ status_t muctx::RenderPage(int page_num, int width, int height,
 	Point page_size;
 	fz_context *ctx_clone = NULL;
 
+	if (mu_dlist == NULL && use_dlist)
+		return E_FAILURE;
+
 	ctx_clone = fz_clone_context(mu_ctx);
 
 	fz_var(dev);
@@ -433,7 +481,10 @@ status_t muctx::RenderPage(int page_num, int width, int height,
 		pix = fz_new_pixmap_with_data(ctx_clone, fz_device_bgr(ctx_clone), width, height, bmp_data);
 		fz_clear_pixmap_with_value(ctx_clone, pix, 255);
 		dev = fz_new_draw_device(ctx_clone, pix);
-		fz_run_page(mu_doc, page, dev, pctm, NULL);
+		if (use_dlist)
+			fz_run_display_list(mu_dlist, dev, pctm, NULL, NULL);
+		else
+			fz_run_page(mu_doc, page, dev, pctm, NULL);
 	}
 	fz_always(ctx_clone)
 	{
diff --git a/winrt/mupdfwinrt/muctx.h b/winrt/mupdfwinrt/muctx.h
index d35718d9..d22009a0 100644
--- a/winrt/mupdfwinrt/muctx.h
+++ b/winrt/mupdfwinrt/muctx.h
@@ -80,6 +80,8 @@ private:
 	fz_locks_context mu_locks;
 	fz_context *mu_ctx;
 	fz_document *mu_doc;
+	fz_display_list *mu_dlist;
+	int dlist_pagenum;
 	fz_outline *mu_outline;
 	fz_rect mu_hit_bbox[MAX_SEARCH];
 	void FlattenOutline(fz_outline *outline, int level,
@@ -92,7 +94,9 @@ public:
 	status_t InitializeStream(IRandomAccessStream^ readStream, char *ext);
 	int GetPageCount();
 	status_t InitializeContext();
-	status_t RenderPage(int page_num, int width, int height, unsigned char *bmp_data);
+	status_t RenderPage(int page_num, int width, int height, unsigned char *bmp_data, bool use_dlist);
+	status_t CreateDisplayList(int page_num);
+	int GetDisplayListPage(void);
 	Point MeasurePage(int page_num);
 	Point MeasurePage(fz_page *page);
 	int GetLinks(int page_num, sh_vector_link links_vec);
diff --git a/winrt/mupdfwinrt/mudocument.cpp b/winrt/mupdfwinrt/mudocument.cpp
index fb227412..8688d520 100644
--- a/winrt/mupdfwinrt/mudocument.cpp
+++ b/winrt/mupdfwinrt/mudocument.cpp
@@ -162,11 +162,33 @@ Windows::Foundation::IAsyncOperationWithProgress<int, double>^
 	});
 }
 
+/* Create the display list for this page */
+Windows::Foundation::IAsyncOperation<int>^ mudocument::CreateDisplayList(int page_num)
+{
+	return create_async([this, page_num](cancellation_token ct) -> int
+	{
+		if (mu_object.GetDisplayListPage() == page_num)
+			return S_ISOK;
+		std::lock_guard<std::mutex> lock(mutex_lock);
+		status_t code = mu_object.CreateDisplayList(page_num);
+		if (code != S_ISOK)
+		{
+			throw ref new FailureException("Display List Creation Failed");
+		}
+		return code;
+	});
+}
+
+int mudocument::GetDisplayListPage(void)
+{
+	return mu_object.GetDisplayListPage();
+}
+
 /* Pack the page into a bmp stream */
 Windows::Foundation::IAsyncOperation<InMemoryRandomAccessStream^>^
-	mudocument::RenderPageAsync(int page_num, int width, int height)
+	mudocument::RenderPageAsync(int page_num, int width, int height, bool use_dlist)
 {
-	return create_async([this, width, height, page_num](cancellation_token ct) -> InMemoryRandomAccessStream^
+	return create_async([this, width, height, page_num, use_dlist](cancellation_token ct) -> InMemoryRandomAccessStream^
 	{
 		/* Allocate space for bmp */
 		Array<unsigned char>^ bmp_data = ref new Array<unsigned char>(height * 4 * width);
@@ -180,7 +202,8 @@ Windows::Foundation::IAsyncOperation<InMemoryRandomAccessStream^>^
 		std::lock_guard<std::mutex> lock(mutex_lock);
 
 		/* Get raster bitmap stream */
-		status_t code = mu_object.RenderPage(page_num, width, height, &(bmp_data[0]));
+		status_t code = mu_object.RenderPage(page_num, width, height, &(bmp_data[0]),
+											 use_dlist);
 		if (code != S_ISOK)
 		{
 			throw ref new FailureException("Page Rendering Failed");
diff --git a/winrt/mupdfwinrt/mudocument.h b/winrt/mupdfwinrt/mudocument.h
index f452f489..d90d2c9a 100644
--- a/winrt/mupdfwinrt/mudocument.h
+++ b/winrt/mupdfwinrt/mudocument.h
@@ -36,8 +36,9 @@ namespace mupdfwinrt
 			Windows::Foundation::IAsyncOperation<int>^ OpenFileAsync(StorageFile^ file);
 			int GetNumPages(void);
 			Point GetPageSize(int page_num);
+			Windows::Foundation::IAsyncOperation<int>^ mudocument::CreateDisplayList(int page_num);
 			Windows::Foundation::IAsyncOperation<InMemoryRandomAccessStream^>^
-				RenderPageAsync(int page_num, int width, int height);
+				RenderPageAsync(int page_num, int width, int height, bool use_dlist);
 			Windows::Foundation::IAsyncOperationWithProgress<int, double>^
 				SearchDocumentWithProgressAsync(String^ textToFind, int dir, int start_page);
 			String^ ComputeHTML(int page_num);
@@ -47,6 +48,7 @@ namespace mupdfwinrt
 			int ComputeContents(void);
 			ContentItem^ GetContent(int k);
 			int ComputeLinks(int page_num);
+			int GetDisplayListPage(void);
 			Links^ GetLink(int k);
 			bool RequiresPassword();
 			bool ApplyPassword(String^ password);