(svn r8969) -Codechange: rework of the player face bits.

 - introduce a new format (with backward compatability) that is more clear and needs a much simpler face drawer
 - replace tons of ifs/switches/magic numbers by table lookups

1 files changed, 153 insertions, 0 deletions

diff --git a/src/player_face.h b/src/player_face.h
new file mode 100644
index 000000000..b2305bb09
--- /dev/null
+++ b/src/player_face.h
@@ -0,0 +1,153 @@
+/* $Id$ */
+
+/** @file player_face.h Functionality related to the player's face */
+
+#ifndef PLAYER_FACE_H
+#define PLAYER_FACE_H
+
+/** The gender/race combinations that we have faces for */
+enum GenderEthnicity {
+	GENDER_FEMALE    = 0, ///< This bit set means a female, otherwise male
+	ETHNICITY_BLACK  = 1, ///< This bit set means black, otherwise white
+
+	GE_WM = 0,                                         ///< A male of Caucasian origin (white)
+	GE_WF = 1 << GENDER_FEMALE,                        ///< A female of Caucasian origin (white)
+	GE_BM = 1 << ETHNICITY_BLACK,                      ///< A male of African origin (black)
+	GE_BF = 1 << ETHNICITY_BLACK | 1 << GENDER_FEMALE, ///< A female of African origin (black)
+	GE_END,
+};
+DECLARE_ENUM_AS_BIT_SET(GenderEthnicity); ///< See GenderRace as a bitset
+
+/** Bitgroups of the PlayerFace variable */
+enum PlayerFaceVariable {
+	PFV_GENDER,
+	PFV_ETHNICITY,
+	PFV_GEN_ETHN,
+	PFV_HAS_MOUSTACHE,
+	PFV_HAS_TIE_EARRING,
+	PFV_HAS_GLASSES,
+	PFV_EYE_COLOUR,
+	PFV_CHEEKS,
+	PFV_CHIN,
+	PFV_EYEBROWS,
+	PFV_MOUSTACHE,
+	PFV_LIPS,
+	PFV_NOSE,
+	PFV_HAIR,
+	PFV_JACKET,
+	PFV_COLLAR,
+	PFV_TIE_EARRING,
+	PFV_GLASSES,
+	PFV_END
+};
+DECLARE_POSTFIX_INCREMENT(PlayerFaceVariable);
+
+/** Information about the valid values of PlayerFace bitgroups as well as the sprites to draw */
+struct PlayerFaceBitsInfo {
+	byte     offset;               ///< Offset in bits into the PlayerFace
+	byte     length;               ///< Number of bits used in the PlayerFace
+	byte     valid_values[GE_END]; ///< The number of valid values per gender/ethnicity
+	SpriteID first_sprite[GE_END]; ///< The first sprite per gender/ethnicity
+};
+
+/** Lookup table for indices into the PlayerFace, valid ranges and sprites */
+static const PlayerFaceBitsInfo _pf_info[] = {
+	/* Index                   off len   WM  WF  BM  BF         WM     WF     BM     BF */
+	/* PFV_GENDER          */ {  0, 1, {  2,  2,  2,  2 }, {     0,     0,     0,     0 } }, ///< 0 = male, 1 = female
+	/* PFV_ETHNICITY       */ {  1, 2, {  2,  2,  2,  2 }, {     0,     0,     0,     0 } }, ///< 0 = (Western-)Caucasian, 1 = African(-American)/Black
+	/* PFV_GEN_ETHN        */ {  0, 3, {  4,  4,  4,  4 }, {     0,     0,     0,     0 } }, ///< Shortcut to get/set gender _and_ ethnicity
+	/* PFV_HAS_MOUSTACHE   */ {  3, 1, {  2,  0,  2,  0 }, {     0,     0,     0,     0 } }, ///< Females do not have a moustache
+	/* PFV_HAS_TIE_EARRING */ {  3, 1, {  0,  2,  0,  2 }, {     0,     0,     0,     0 } }, ///< Draw the earring for females or not. For males the tie is always drawn.
+	/* PFV_HAS_GLASSES     */ {  4, 1, {  2,  2,  2,  2 }, {     0,     0,     0,     0 } }, ///< Whether to draw glasses or not
+	/* PFV_EYE_COLOUR      */ {  5, 2, {  3,  3,  3,  3 }, {     0,     0,     0,     0 } }, ///< Palette modification
+	/* PFV_CHEEKS          */ {  0, 0, {  1,  1,  1,  1 }, { 0x325, 0x326, 0x390, 0x3B0 } }, ///< Cheeks are only indexed by their gender/ethnicity
+	/* PFV_CHIN            */ {  7, 2, {  4,  1,  2,  2 }, { 0x327, 0x327, 0x391, 0x3B1 } },
+	/* PFV_EYEBROWS        */ {  9, 4, { 12, 16, 11, 16 }, { 0x32B, 0x337, 0x39A, 0x3B8 } },
+	/* PFV_MOUSTACHE       */ { 13, 2, {  3,  0,  3,  0 }, { 0x367,     0, 0x397,     0 } }, ///< Depends on PFV_HAS_MOUSTACHE
+	/* PFV_LIPS            */ { 13, 4, { 13, 10,  9,  9 }, { 0x35B, 0x351, 0x3A5, 0x3C8 } }, ///< Depends on !PFV_HAS_MOUSTACHE
+	/* PFV_NOSE            */ { 17, 3, {  8,  4,  4,  5 }, { 0x349, 0x34C, 0x393, 0x3B3 } }, ///< Depends on !PFV_HAS_MOUSTACHE
+	/* PFV_HAIR            */ { 20, 4, {  9,  5,  5,  4 }, { 0x382, 0x38B, 0x3D4, 0x3D9 } },
+	/* PFV_JACKET          */ { 24, 2, {  3,  3,  3,  3 }, { 0x36B, 0x378, 0x36B, 0x378 } },
+	/* PFV_COLLAR          */ { 26, 2, {  4,  4,  4,  4 }, { 0x36E, 0x37B, 0x36E, 0x37B } },
+	/* PFV_TIE_EARRING     */ { 28, 3, {  6,  3,  6,  3 }, { 0x372, 0x37F, 0x372, 0x3D1 } }, ///< Depends on PFV_HAS_TIE_EARRING
+	/* PFV_GLASSES         */ { 31, 1, {  2,  2,  2,  2 }, { 0x347, 0x347, 0x3AE, 0x3AE } }  ///< Depends on PFV_HAS_GLASSES
+};
+assert_compile(lengthof(_pf_info) == PFV_END);
+
+/**
+ * Gets the player's face bits for the given player face variable
+ * @param pf  the face to extract the bits from
+ * @param pfv the face variable to get the data of
+ * @param ge  the gender and ethnicity of the face
+ * @pre _pf_info[pfv].valid_values[ge] != 0
+ * @return the requested bits
+ */
+static inline uint GetPlayerFaceBits(PlayerFace pf, PlayerFaceVariable pfv, GenderEthnicity ge)
+{
+	assert(_pf_info[pfv].valid_values[ge] != 0);
+
+	return GB(pf, _pf_info[pfv].offset, _pf_info[pfv].length);
+}
+
+/**
+ * Sets the player's face bits for the given player face variable
+ * @param pf  the face to write the bits to
+ * @param pfv the face variable to write the data of
+ * @param ge  the gender and ethnicity of the face
+ * @param val the new value
+ * @pre val < _pf_info[pfv].valid_values[ge]
+ */
+static inline void SetPlayerFaceBits(PlayerFace &pf, PlayerFaceVariable pfv, GenderEthnicity ge, uint val)
+{
+	assert(val < _pf_info[pfv].valid_values[ge]);
+
+	SB(pf, _pf_info[pfv].offset, _pf_info[pfv].length, val);
+}
+
+/**
+ * Checks whether the player bits have a valid range
+ * @param pf  the face to extract the bits from
+ * @param pfv the face variable to get the data of
+ * @param ge  the gender and ethnicity of the face
+ * @return true if and only if the bits are valid
+ */
+static inline bool ArePlayerFaceBitsValid(PlayerFace pf, PlayerFaceVariable pfv, GenderEthnicity ge)
+{
+	return GB(pf, _pf_info[pfv].offset, _pf_info[pfv].length) < _pf_info[pfv].valid_values[ge];
+}
+
+/**
+ * Scales a player face bits variable to the correct scope
+ * @param pfv the face variable to write the data of
+ * @param ge  the gender and ethnicity of the face
+ * @param val the to value to scale
+ * @pre val < (1U << _pf_info[pfv].length), i.e. val has a value of 0..2^(bits used for this variable)-1
+ * @return the scaled value
+ */
+static inline uint ScalePlayerFaceValue(PlayerFaceVariable pfv, GenderEthnicity ge, uint val)
+{
+	assert(val < (1U << _pf_info[pfv].length));
+
+	return (val * _pf_info[pfv].valid_values[ge]) >> _pf_info[pfv].length;
+}
+
+/**
+ * Gets the sprite to draw for the given player face variable
+ * @param pf  the face to extract the data from
+ * @param pfv the face variable to get the sprite of
+ * @param ge  the gender and ethnicity of the face
+ * @pre _pf_info[pfv].valid_values[ge] != 0
+ * @return sprite to draw
+ */
+static inline SpriteID GetPlayerFaceSprite(PlayerFace pf, PlayerFaceVariable pfv, GenderEthnicity ge)
+{
+	assert(_pf_info[pfv].valid_values[ge] != 0);
+
+	return _pf_info[pfv].first_sprite[ge] + GB(pf, _pf_info[pfv].offset, _pf_info[pfv].length);
+}
+
+void DrawPlayerFace(PlayerFace face, int color, int x, int y);
+PlayerFace ConvertFromOldPlayerFace(uint32 face);
+bool IsValidPlayerFace(PlayerFace pf);
+
+#endif /* PLAYER_FACE_H */