Tweak scale factors, and fix one reference count error.

Consider rotated pages when calculating the fit page to screen scaling
factors. Also adjust the scale factors to always map the mediabox to an
integral number of pixels.

1 files changed, 47 insertions, 29 deletions

diff --git a/ios/main.m b/ios/main.m
index 72cbaa42..7ec452e5 100644
--- a/ios/main.m
+++ b/ios/main.m
@@ -14,7 +14,6 @@
 static dispatch_queue_t queue;
 static fz_glyph_cache *glyphcache = NULL;
 static UIImage *loadingImage = nil;
-static NSString *docdir = nil;
 
 @interface MuLibraryController : UITableViewController
 {
@@ -36,8 +35,8 @@ static NSString *docdir = nil;
 
 @interface MuDocumentController : UIViewController <UIScrollViewDelegate>
 {
-	NSString *key;
 	pdf_xref *xref;
+	NSString *key;
 	MuOutlineController *outline;
 	UIScrollView *canvas;
 	UILabel *indicator;
@@ -110,7 +109,7 @@ static void loadOutlineImp(NSMutableArray *titles, NSMutableArray *pages, pdf_xr
 	memset(buf, ' ', level * 4);
 	while (outline)
 	{
-		int number =  pageNumberFromLink(xref, outline->link);
+		int number = pageNumberFromLink(xref, outline->link);
 		if (number >= 0) {
 			[titles addObject: [NSString stringWithFormat: @"%s%s", buf, outline->title]];
 			[pages addObject: [NSNumber numberWithInt: number]];
@@ -147,17 +146,31 @@ static UIImage *newImageWithPixmap(fz_pixmap *pix)
 	return image;
 }
 
-static UIImage *renderPage(pdf_xref *xref, int number, float width, float height)
+static CGSize fitPageToScreen(CGSize page, CGSize screen)
 {
+	float hscale = screen.width / page.width;
+	float vscale = screen.height / page.height;
+	float scale = MIN(hscale, vscale);
+	float new_w = floorf(page.width * scale);
+	float new_h = floorf(page.height * scale);
+	hscale = new_w / page.width;
+	vscale = new_h / page.height;
+	return CGSizeMake(hscale, vscale);
+}
+
+static UIImage *renderPage(pdf_xref *xref, int number, CGSize screen)
+{
+	fz_error error;
+	CGSize pagesize;
+	fz_rect mediabox;
 	fz_bbox bbox;
 	fz_matrix ctm;
 	fz_device *dev;
 	fz_pixmap *pix;
 	pdf_page *page;
-	fz_error error;
-	float scale, hscale, vscale;
+	CGSize scale;
 
-	printf("loading page %d [%g %g]\n", number, width, height);
+	printf("loading page %d\n", number);
 
 	error = pdf_load_page(&page, xref, number);
 	if (error) {
@@ -165,12 +178,12 @@ static UIImage *renderPage(pdf_xref *xref, int number, float width, float height
 		return nil;
 	}
 
-	hscale = width / (page->mediabox.x1 - page->mediabox.x0);
-	vscale = height / (page->mediabox.y1 - page->mediabox.y0);
-	scale = MIN(hscale, vscale);
+	mediabox = fz_transform_rect(fz_rotate(page->rotate), page->mediabox);
+	pagesize = CGSizeMake(mediabox.x1 - mediabox.x0, mediabox.y1 - mediabox.y0);
+	scale = fitPageToScreen(pagesize, screen);
 
 	ctm = fz_translate(0, -page->mediabox.y1);
-	ctm = fz_concat(ctm, fz_scale(scale, -scale));
+	ctm = fz_concat(ctm, fz_scale(scale.width, -scale.height));
 	ctm = fz_concat(ctm, fz_rotate(page->rotate));
 	bbox = fz_round_rect(fz_transform_rect(ctm, page->mediabox));
 
@@ -194,25 +207,24 @@ static UIImage *renderPage(pdf_xref *xref, int number, float width, float height
 
 - (void) viewWillAppear: (BOOL)animated
 {
+	[self setTitle: @"MuPDF"];
 	[self reload];
-
+	printf("library viewWillAppear (starting reload timer)\n");
 	timer = [NSTimer timerWithTimeInterval: 1
 		target: self selector: @selector(reload) userInfo: nil
 		repeats: YES];
-
 	[[NSRunLoop currentRunLoop] addTimer: timer forMode: NSDefaultRunLoopMode];
 }
 
 - (void) viewWillDisappear: (BOOL)animated
 {
+	printf("library viewWillDisappear (stopping reload timer)\n");
 	[timer invalidate];
 	timer = nil;
 }
 
 - (void) reload
 {
-	[self setTitle: @"MuPDF"];
-
 	NSError *error = nil;
 
 	if (files) {
@@ -220,6 +232,7 @@ static UIImage *renderPage(pdf_xref *xref, int number, float width, float height
 		files = nil;
 	}
 
+	NSString *docdir = [NSString stringWithFormat: @"%@/Documents", NSHomeDirectory()];
 	files = [[NSFileManager defaultManager] contentsOfDirectoryAtPath: docdir error: &error];
 	if (error)
 		files = [NSArray arrayWithObjects: @"...error loading directory...", nil];
@@ -295,7 +308,7 @@ static UIImage *renderPage(pdf_xref *xref, int number, float width, float height
 	self = [super initWithStyle: UITableViewStylePlain];
 	if (self) {
 		[self setTitle: @"Table of Contents"];
-		target = [aTarget retain];
+		target = aTarget; // only keep a weak reference, to avoid retain cycles
 		titles = [aTitles retain];
 		pages = [aPages retain];
 	}
@@ -372,8 +385,8 @@ static UIImage *renderPage(pdf_xref *xref, int number, float width, float height
 
 	dispatch_sync(queue, ^{});
 
-	strcpy(filename, [docdir UTF8String]);
-	strcat(filename, "/");
+	strcpy(filename, [NSHomeDirectory() UTF8String]);
+	strcat(filename, "/Documents/");
 	strcat(filename, [nsfilename UTF8String]);
 
 	printf("open xref '%s'\n", filename);
@@ -547,7 +560,7 @@ static UIImage *renderPage(pdf_xref *xref, int number, float width, float height
 
 	dispatch_async(queue, ^{
 		if (pageviews[number]) {
-			UIImage *image = renderPage(xref, number, width - GAP, height);
+			UIImage *image = renderPage(xref, number, CGSizeMake(width - GAP, height));
 			dispatch_async(dispatch_get_main_queue(), ^{
 				if (pageviews[number]) {
 					[pageviews[number] setImage: image];
@@ -567,13 +580,13 @@ static UIImage *renderPage(pdf_xref *xref, int number, float width, float height
 		UIImageView *page = pageviews[number];
 		UIImage *image = [page image];
 		if (image != loadingImage) {
-			CGRect frame = [page frame];
-			CGSize pagesize = [image size];
-			float scale = MIN((width - GAP) / pagesize.width, height / pagesize.height);
-			if (fabs(scale - 1) > 0.1) {
+			CGSize imagesize = [image size];
+			CGSize scale = fitPageToScreen(imagesize, CGSizeMake(width-GAP, height));
+			if (fabs(scale.width - 1) > 0.1) {
 				[self reloadPage: number];
-				frame.size.width = pagesize.width * scale;
-				frame.size.height = pagesize.height * scale;
+				CGRect frame = [page frame];
+				frame.size.width = imagesize.width * scale.width;
+				frame.size.height = imagesize.height * scale.height;
 				[page setFrame: frame];
 			} else {
 				[page sizeToFit];
@@ -581,7 +594,15 @@ static UIImage *renderPage(pdf_xref *xref, int number, float width, float height
 		} else {
 			[page sizeToFit];
 		}
-		[page setCenter: CGPointMake(number * width + (width-GAP)/2, height/2)];
+
+		// We can't use setCenter because we'll end up with a
+		// misaligned and blurry image on odd pixel sizes
+		CGRect frame = [page frame];
+		frame.origin.x = number * width;
+		frame.origin.y = 0;
+		frame.origin.x += floor((width-GAP - frame.size.width) / 2);
+		frame.origin.y += floor((height - frame.size.height) / 2);
+		[page setFrame: frame];
 	}
 }
 
@@ -766,9 +787,6 @@ static UIImage *renderPage(pdf_xref *xref, int number, float width, float height
 
 	glyphcache = fz_new_glyph_cache();
 
-	NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
-	docdir = [[paths objectAtIndex: 0] retain];
-
 	loadingImage = [[UIImage imageNamed: @"loading.png"] retain];
 
 	library = [[MuLibraryController alloc] initWithStyle: UITableViewStylePlain];