Further minor tweaks to TiledLibreOffice

Change-Id: If1c1bbaadf8866605bf1026c4a71da0a397391a4

ios/experimental/TiledLibreOffice/TiledLibreOffice/TiledView.h

@@ -10,7 +10,7 @@
 
 @interface TiledView : UIView
 
-- (id)initWithFrame:(CGRect)frame andScale:(CGFloat)scale;
+- (id)initWithFrame:(CGRect)frame scale:(CGFloat)scale maxZoom:(int)maxZoom;
 
 @end
 

ios/experimental/TiledLibreOffice/TiledLibreOffice/TiledView.m

@@ -19,15 +19,15 @@
 
 @implementation TiledView
 
-- (id)initWithFrame:(CGRect)frame andScale:(CGFloat)scale
+- (id)initWithFrame:(CGRect)frame scale:(CGFloat)scale maxZoom:(int)maxZoom
 {
     self = [super initWithFrame:frame];
     if (self) {
         self.scale = scale;
         CATiledLayer *catl = (CATiledLayer*) [self layer];
         catl.tileSize = CGSizeMake(512, 512);
-        catl.levelsOfDetail = 4;
-        catl.levelsOfDetailBias = 4;
+        catl.levelsOfDetail = log2(maxZoom) + 1;
+        catl.levelsOfDetailBias = catl.levelsOfDetail - 1;
     }
     return self;
 }
@@ -39,22 +39,46 @@
 
 - (void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx
 {
-    CGContextSaveGState(ctx);
+    // Even if I set the CATL's tileSize to 512x512 above, this is
+    // called initially with a clip bbox of 128x128. Odd, I would have
+    // expected it to be called with a bbox of 256x256.
 
     CGRect bb = CGContextGetClipBoundingBox(ctx);
+    double zoomScale = [(View *) [self superview] zoomScale];
+    CATiledLayer *catl = (CATiledLayer*) [self layer];
 
-    // NSLog(@"%.0fx%.0f@(%.0f,%.0f) %f", bb.size.width, bb.size.height, bb.origin.x, bb.origin.y, 1/[(View *) [self superview] zoomScale]);
+    CGContextSaveGState(ctx);
 
     CGContextTranslateCTM(ctx, bb.origin.x, bb.origin.y);
+    // CGContextScaleCTM(ctx, 1/zoomScale, 1/zoomScale);
 
-    NSLog(@"tile:%.0fx%.0f at:(%.0f,%.0f) size:%.0fx%.0f", bb.size.width, bb.size.height, bb.origin.x/self.scale, bb.origin.y/self.scale, bb.size.width/self.scale, bb.size.height/self.scale);
+    // CGSize tileSize = [catl tileSize];
+    CGSize tileSize = bb.size;
+
+    // NSLog(@"bb:%.0fx%.0f@(%.0f,%.0f) zoomScale:%.0f tile:%.0fx%.0f at:(%.0f,%.0f) size:%.0fx%.0f", bb.size.width, bb.size.height, bb.origin.x, bb.origin.y, zoomScale, tileSize.width, tileSize.height, bb.origin.x/self.scale, bb.origin.y/self.scale, bb.size.width/self.scale, bb.size.height/self.scale);
+
+    // I don't really claim to fully understand all this. It does seem
+    // a bit weird to be passing in a "context width x height" (in the
+    // terminology of touch_lo_draw_tile) of 64x64, for instance, even
+    // if that tile is actually going to be rendered to 128x128 actual
+    // pixels. But this seems to work. Other combinations, applying
+    // scaling to the CTM, etc, don't. But maybe I haven't tried hard
+    // enough.
 
     touch_lo_draw_tile(ctx,
-                       bb.size.width, bb.size.height,
+                       tileSize.width, tileSize.height,
                        CGPointMake(bb.origin.x/self.scale, bb.origin.y/self.scale),
                        CGSizeMake(bb.size.width/self.scale, bb.size.height/self.scale));
 
     CGContextRestoreGState(ctx);
+
+    // I am a bit confused about what tiles exactly I am drawing, so
+    // make it perfectly obvious by drawing borders around the tiles
+    CGContextSaveGState(ctx);
+    CGContextSetStrokeColorWithColor(ctx, [[UIColor colorWithRed:1 green:0 blue:0 alpha:0.5] CGColor]);
+    CGContextSetLineWidth(ctx, 1);
+    CGContextStrokeRect(ctx, bb);
+    CGContextRestoreGState(ctx);
 }
 
 @end

ios/experimental/TiledLibreOffice/TiledLibreOffice/View.m

@@ -23,7 +23,9 @@
 {
     self = [super initWithFrame:frame];
     if (self) {
-        [self setMaximumZoomScale:4];
+        const int MAXZOOM = 4;
+
+        [self setMaximumZoomScale:MAXZOOM];
         [self setDelegate:self];
 
         MLODpxSize docSize = touch_lo_get_content_size();
@@ -31,9 +33,9 @@
         double widthScale = frame.size.width / docSize.width;
         double docAspectRatio = docSize.height / docSize.width;
 
-        NSLog(@"View frame=%.0fx%.0f docSize=%.0fx%.0f scale=%.3f aspectRatio=%.3f", frame.size.width, frame.size.height, docSize.width, docSize.height, widthScale, docAspectRatio);
+        // NSLog(@"View frame=%.0fx%.0f docSize=%.0fx%.0f scale=%.3f aspectRatio=%.3f", frame.size.width, frame.size.height, docSize.width, docSize.height, widthScale, docAspectRatio);
 
-        self.subView = [[TiledView alloc] initWithFrame:CGRectMake(0, 0, frame.size.width, frame.size.width*docAspectRatio) andScale:widthScale];
+        self.subView = [[TiledView alloc] initWithFrame:CGRectMake(0, 0, frame.size.width, frame.size.width*docAspectRatio) scale:widthScale maxZoom:MAXZOOM];
         [self addSubview:self.subView];
     }
     return self;
@@ -44,14 +46,6 @@
     return self.subView;
 }
 
-- (void)scrollViewWillBeginZooming:(UIScrollView *)scrollView withView:(UIView *)view
-{
-}
-
-- (void)scrollViewDidEndZooming:(UIScrollView *)scrollView withView:(UIView *)view atScale:(CGFloat)scale
-{
-}
-
 @end
 
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