Fix font loading:

Fixes bug #2058539: OS: Assert starting demo (regression).
May possibly also fix bug #2019344: FW: crash with Amiga Italian version (photocopy room),
but not sure about that because I couldn't reproduce the bug myself.

svn-id: r34065

3 files changed, 33 insertions, 20 deletions

diff --git a/engines/cine/gfx.cpp b/engines/cine/gfx.cpp
index 5a94d57311..c5799e0e62 100644
--- a/engines/cine/gfx.cpp
+++ b/engines/cine/gfx.cpp
@@ -368,7 +368,7 @@ int FWRenderer::drawChar(char character, int x, int y) {
 		x += 5;
 	} else if ((width = g_cine->_textHandler.fontParamTable[(unsigned char)character].characterWidth)) {
 		idx = g_cine->_textHandler.fontParamTable[(unsigned char)character].characterIdx;
-		drawSpriteRaw(g_cine->_textHandler.textTable[idx][0], g_cine->_textHandler.textTable[idx][1], 16, 8, _backBuffer, x, y);
+		drawSpriteRaw(g_cine->_textHandler.textTable[idx][FONT_DATA], g_cine->_textHandler.textTable[idx][FONT_MASK], FONT_WIDTH, FONT_HEIGHT, _backBuffer, x, y);
 		x += width + 1;
 	}
 
@@ -1040,7 +1040,7 @@ int OSRenderer::drawChar(char character, int x, int y) {
 		x += 5;
 	} else if ((width = g_cine->_textHandler.fontParamTable[(unsigned char)character].characterWidth)) {
 		idx = g_cine->_textHandler.fontParamTable[(unsigned char)character].characterIdx;
-		drawSpriteRaw2(g_cine->_textHandler.textTable[idx][0], 0, 16, 8, _backBuffer, x, y);
+		drawSpriteRaw2(g_cine->_textHandler.textTable[idx][FONT_DATA], 0, FONT_WIDTH, FONT_HEIGHT, _backBuffer, x, y);
 		x += width + 1;
 	}
 
diff --git a/engines/cine/texte.cpp b/engines/cine/texte.cpp
index 33c16159ec..c8d48d3a06 100644
--- a/engines/cine/texte.cpp
+++ b/engines/cine/texte.cpp
@@ -39,6 +39,13 @@ const char **commandPrepositionTable;
 
 void generateMask(const byte *sprite, byte *mask, uint16 size, byte transparency);
 
+/*! \brief Loads font data from the given file.
+ * The number of characters used in the font varies between game versions:
+ * 78 (Most PC, Amiga and Atari ST versions of Future Wars, but also Operation Stealth's Amiga demo),
+ * 85 (All observed versions of German Future Wars (Amiga and PC), possibly Spanish Future Wars too),
+ * 90 (Most PC, Amiga and Atari ST versions of Operation Stealth),
+ * 93 (All observed versions of German Operation Stealth (Amiga and PC)).
+ */
 void loadTextData(const char *filename) {
 	Common::File fileHandle;
 	assert(filename);
@@ -46,30 +53,29 @@ void loadTextData(const char *filename) {
 	if (!fileHandle.open(filename))
 		error("loadTextData(): Cannot open file %s", filename);
 
-	uint entrySize = fileHandle.readUint16BE();
-	uint numEntry = fileHandle.readUint16BE();
+	static const uint headerSize = 2 + 2;              // The entry size (16-bit) and entry count (16-bit).
+	const uint entrySize = fileHandle.readUint16BE();  // Observed values: 8.
+	const uint entryCount = fileHandle.readUint16BE(); // Observed values: 624, 680, 720, 744.
+	const uint fontDataSize = entryCount * entrySize;  // Observed values: 4992, 5440, 5760, 5952.
+	const uint numChars = entryCount / entrySize;      // Observed values: 78, 85, 90, 93.
+	const uint bytesPerChar = fontDataSize / numChars; // Observed values: 64.
+	static const uint bytesPerRow = FONT_WIDTH / 2;    // The input font data is 4-bit so it takes only half the space
+
+	if (headerSize + fontDataSize != fileHandle.size()) {
+		warning("loadTextData: file '%s' (entrySize = %d, entryCount = %d) is of incorrect size %d", filename, entrySize, entryCount, fileHandle.size());
+	}
 
-	uint sourceSize = numEntry * entrySize;
 	Common::Array<byte> source;
-	source.resize(sourceSize);
-	fileHandle.read(source.begin(), sourceSize);
+	source.resize(fontDataSize);
+	fileHandle.read(source.begin(), fontDataSize);
 
-	const int fontHeight = 8;
-	const int fontWidth = (g_cine->getGameType() == Cine::GType_FW) ? 16 : 8;
-	uint numCharacters;
-	uint bytesPerCharacter;
 	if (g_cine->getGameType() == Cine::GType_FW) {
-		numCharacters = (g_cine->getFeatures() & GF_ALT_FONT) ? 85 : 78;		
-		bytesPerCharacter = sourceSize / numCharacters; // TODO: Check if this could be replaced with fontWidth * fontHeight
 		loadRelatedPalette(filename);
-	} else {
-		numCharacters = 90;
-		bytesPerCharacter = fontWidth * fontHeight;
 	}
 
-	for (uint i = 0; i < numCharacters; i++) {
-		gfxConvertSpriteToRaw(g_cine->_textHandler.textTable[i][0], &source[i * bytesPerCharacter], fontWidth, fontHeight);
-		generateMask(g_cine->_textHandler.textTable[i][0], g_cine->_textHandler.textTable[i][1], fontWidth * fontHeight, 0);
+	for (uint i = 0; i < numChars; i++) {
+		gfxConvertSpriteToRaw(g_cine->_textHandler.textTable[i][FONT_DATA], &source[i * bytesPerChar], bytesPerRow, FONT_HEIGHT);
+		generateMask(g_cine->_textHandler.textTable[i][FONT_DATA], g_cine->_textHandler.textTable[i][FONT_MASK], FONT_WIDTH * FONT_HEIGHT, 0);
 	}
 
 	fileHandle.close();
diff --git a/engines/cine/texte.h b/engines/cine/texte.h
index bc4beac492..0b1fc88e86 100644
--- a/engines/cine/texte.h
+++ b/engines/cine/texte.h
@@ -36,13 +36,20 @@ typedef char CommandeType[20];
 // Number of characters in a font
 #define NUM_FONT_CHARS 256
 
+#define FONT_WIDTH 16
+#define FONT_HEIGHT 8
+
+// Used for choosing between font's data and font's mask
+#define FONT_DATA 0
+#define FONT_MASK 1
+
 struct CharacterEntry {
 	byte characterIdx;
 	byte characterWidth;
 };
 
 struct TextHandler {
-	byte textTable[NUM_FONT_CHARS][2][16 * 8];
+	byte textTable[NUM_FONT_CHARS][2][FONT_WIDTH * FONT_HEIGHT];
 	CharacterEntry fontParamTable[NUM_FONT_CHARS];
 };