Fix drawing of B_GRAY1 bitmaps.

- Colors were reversed - Padding was not handled properly because of a roundeing error Add a test that shows the issue (behavior confirmed against BeOS) Change-Id: I4c6e954fb6bdab92ad4e0e96897e78b26eb4727b Reviewed-on: https://review.haiku-os.org/c/1025 Reviewed-by: Stephan Aßmus <[email protected]>
2019-02-10 09:59:38 +00:00
parent 8341933096
commit e89985cc31
3 changed files with 110 additions and 14 deletions
@@ -0,0 +1,90 @@
+/*
+ * Copyright 2019, Adrien Destugues <[email protected]>
+ * Distributed under terms of the MIT license.
+ */
+
+
+#include <Application.h>
+#include <Bitmap.h>
+#include <View.h>
+#include <Window.h>
+
+#include <assert.h>
+
+
+class BitmapView: public BView
+{
+	public:
+		BitmapView(BBitmap* bitmap)
+			: BView(bitmap->Bounds(), "test view", B_FOLLOW_LEFT_TOP, B_WILL_DRAW)
+			, fBitmap(bitmap)
+		{
+		}
+
+		~BitmapView()
+		{
+			delete fBitmap;
+		}
+
+		void Draw(BRect updateRect)
+		{
+			DrawBitmap(fBitmap);
+		}
+
+	private:
+		BBitmap* fBitmap;
+};
+
+
+int
+main(void)
+{
+	BApplication app("application/Haiku-BitmapTest");
+
+	BWindow* window = new BWindow(BRect(10, 10, 100, 100),
+		"Bitmap drawing test", B_DOCUMENT_WINDOW, B_QUIT_ON_WINDOW_CLOSE);
+	window->Show();
+
+	BBitmap* bitmap = new BBitmap(BRect(0, 0, 24, 24), B_GRAY1);
+
+	// Bitmap is 25 pixels wide, which rounds up to 4 pixels
+	// The last byte only has one bit used, and 7 bits of padding
+	assert(bitmap->BytesPerRow() == 4);
+
+	// This was extracted from letter_a.pbm and should look mostly like a
+	// black "A" letter on a white background (confirmed BeOS behavior)
+	const unsigned char data[] = {
+		0, 0, 0, 0,
+		0, 8, 0, 0,
+		0, 0x1c, 0, 0,
+		0, 0x3e, 0, 0,
+		0, 0x7e, 0, 0,
+		0, 0xFF, 0, 0,
+		0, 0xE7, 0, 0,
+		0, 0xC3, 0, 0,
+		1, 0xC3, 0x80, 0,
+		1, 0x81, 0x80, 0,
+		3, 0x81, 0xC0, 0,
+		3, 0xFF, 0xC0, 0,
+		7, 0xFF, 0xE0, 0,
+		7, 0xFF, 0xE0, 0,
+		7, 0x81, 0xE0, 0,
+		0x0F, 0, 0x0F, 0,
+		0x0F, 0, 0x0F, 0,
+		0x1F, 0, 0xF8, 0,
+		0x1E, 0, 0x78, 0,
+		0x1C, 0, 0x38, 0,
+		0x3C, 0, 0x3C, 0,
+		0x3C, 0, 0x3C, 0,
+		0x38, 0, 0x0E, 0,
+		0x78, 0, 0x0F, 0,
+		0, 0, 0, 0
+	};
+	bitmap->SetBits(data, sizeof(data), 0, B_GRAY1);
+
+	BView* view = new BitmapView(bitmap);
+	window->AddChild(view);
+
+	app.Run();
+	return 0;
+}