Implement base palette ID

include/gfx/main.hpp

@@ -43,6 +43,7 @@ struct Options {
 		uint32_t right() const { return left + width * 8; }
 		uint32_t bottom() const { return top + height * 8; }
 	} inputSlice{0, 0, 0, 0};                          // -L (margins in clockwise order, like CSS)
+	uint8_t basePalID = 0;                             // -l
 	std::array<uint16_t, 2> maxNbTiles{UINT16_MAX, 0}; // -N
 	uint16_t nbPalettes = 8;                           // -n
 	std::string output{};                              // -o

man/rgbgfx.1

@@ -18,6 +18,7 @@
 .Op Fl d Ar depth
 .Op Fl i Ar input_tiles
 .Op Fl L Ar slice
+.Op Fl l Ar base_pal
 .Op Fl N Ar nb_tiles
 .Op Fl n Ar nb_pals
 .Op Fl o Ar out_file
@@ -261,6 +262,11 @@ The first number pair specifies the X and Y coordinates of the top-left pixel th
 The second number pair specifies how many tiles to process horizontally and vertically, respectively.
 .Pp
 .Fl L Sy is ignored in reverse mode , No no padding is inserted .
+.It Fl l Ar base_pal , Fl \-base-palette Ar base_pal
+Set the base ID for attribute map and palette map output.
+.Ar base_pal
+should be a number between 0 and 255.
+It defaults to 0.
 .It Fl m , Fl \-mirror-tiles
 Deduplicate tiles that are horizontally and/or vertically symmetrical mirror images of each other.
 Only one of each unique tile will be saved in the tile data file, with mirror images counting as duplicates.

src/gfx/main.cpp

@@ -113,7 +113,7 @@ void Options::verbosePrint(uint8_t level, char const *fmt, ...) const {
 }
 
 // Short options
-static char const *optstring = "-Aa:B:b:Cc:d:hi:L:mN:n:Oo:Pp:Qq:r:s:Tt:U:uVvXx:YZ";
+static char const *optstring = "-Aa:B:b:Cc:d:hi:L:l:mN:n:Oo:Pp:Qq:r:s:Tt:U:uVvXx:YZ";
 
 // Equivalent long options
 // Please keep in the same order as short opts.
@@ -133,6 +133,7 @@ static option const longopts[] = {
     {"help",             no_argument,       nullptr, 'h'},
     {"input-tileset",    required_argument, nullptr, 'i'},
     {"slice",            required_argument, nullptr, 'L'},
+    {"base-palette",     required_argument, nullptr, 'l'},
     {"mirror-tiles",     no_argument,       nullptr, 'm'},
     {"nb-tiles",         required_argument, nullptr, 'N'},
     {"nb-palettes",      required_argument, nullptr, 'n'},
@@ -162,9 +163,9 @@ static void printUsage() {
 	fputs(
 	    "Usage: rgbgfx [-r stride] [-ChmOuVXYZ] [-v [-v ...]] [-a <attr_map> | -A]\n"
 	    "       [-b <base_ids>] [-c <colors>] [-d <depth>] [-i <tileset_file>]\n"
-	    "       [-L <slice>] [-N <nb_tiles>] [-n <nb_pals>] [-o <out_file>]\n"
-	    "       [-p <pal_file> | -P] [-q <pal_map> | -Q] [-s <nb_colors>]\n"
-	    "       [-t <tile_map> | -T] [-x <nb_tiles>] <file>\n"
+	    "       [-L <slice>] [-l <base_pal>] [-N <nb_tiles>] [-n <nb_pals>]\n"
+	    "       [-o <out_file>] [-p <pal_file> | -P] [-q <pal_map> | -Q]\n"
+	    "       [-s <nb_colors>] [-t <tile_map> | -T] [-x <nb_tiles>] <file>\n"
 	    "Useful options:\n"
 	    "    -m, --mirror-tiles    optimize out mirrored tiles\n"
 	    "    -o, --output <path>   output the tile data to this path\n"
@@ -481,6 +482,16 @@ static char *parseArgv(int argc, char *argv[]) {
 				error("Unexpected extra characters after slice spec in \"%s\"", musl_optarg);
 			}
 			break;
+		case 'l':
+			number = parseNumber(arg, "Base palette ID", 0);
+			if (*arg != '\0') {
+				error("Base palette ID must be a valid number, not \"%s\"", musl_optarg);
+			} else if (number >= 256) {
+				error("Base palette ID must be below 256");
+			} else {
+				options.basePalID = number;
+			}
+			break;
 		case 'm':
 			options.allowMirroringX = true; // Imply `-X`
 			options.allowMirroringY = true; // Imply `-Y`
@@ -876,6 +887,7 @@ int main(int argc, char *argv[]) {
 		    options.baseTileIDs[0],
 		    options.baseTileIDs[1]
 		);
+		fprintf(stderr, "\tBase palette ID: %" PRIu8 "\n", options.basePalID);
 		fprintf(
 		    stderr,
 		    "\tMaximum %" PRIu16 " tiles in bank 0, %" PRIu16 " in bank 1\n",

src/gfx/process.cpp

@@ -928,9 +928,9 @@ static void outputUnoptimizedMaps(
 			(*tilemapOutput)
 			    ->sputc((attr.isBackgroundTile() ? 0 : tileID) + options.baseTileIDs[bank]);
 		}
-		uint8_t palID = attr.getPalID(mappings);
+		uint8_t palID = attr.getPalID(mappings) + options.basePalID;
 		if (attrmapOutput.has_value()) {
-			(*attrmapOutput)->sputc((palID & 7) | bank << 3); // The other flags are all 0
+			(*attrmapOutput)->sputc((palID & 0b111) | bank << 3); // The other flags are all 0
 		}
 		if (palmapOutput.has_value()) {
 			(*palmapOutput)->sputc(palID);
@@ -1112,7 +1112,7 @@ static void outputAttrmap(
 	for (AttrmapEntry const &entry : attrmap) {
 		uint8_t attr = entry.xFlip << 5 | entry.yFlip << 6;
 		attr |= entry.bank << 3;
-		attr |= entry.getPalID(mappings) & 7;
+		attr |= (entry.getPalID(mappings) + options.basePalID) & 0b111;
 		output->sputc(attr);
 	}
 }
@@ -1128,7 +1128,7 @@ static void outputPalmap(
 	}
 
 	for (AttrmapEntry const &entry : attrmap) {
-		output->sputc(entry.getPalID(mappings));
+		output->sputc(entry.getPalID(mappings) + options.basePalID);
 	}
 }
 

src/gfx/reverse.cpp

@@ -289,10 +289,10 @@ void reverse() {
 			uint8_t attr = (*attrmap)[index];
 			size_t tx = index % width, ty = index / width;
 
-			if ((attr & 0b111) > palettes.size()) {
+			if (uint8_t palID = (attr & 0b111) - options.basePalID; palID > palettes.size()) {
 				error(
 				    "Attribute map references palette #%u at (%zu, %zu), but there are only %zu!",
-				    attr & 0b111,
+				    palID,
 				    tx,
 				    ty,
 				    palettes.size()
@@ -356,7 +356,7 @@ void reverse() {
 				size_t tx = index % width, ty = index / width;
 				uint8_t tileID = (*tilemap)[index];
 				uint8_t attr = (*attrmap)[index];
-				bool bank = attr & 0x08;
+				bool bank = attr & 0b1000;
 
 				if (uint8_t tileOfs = tileID - options.baseTileIDs[bank];
 				    tileOfs >= options.maxNbTiles[bank]) {
@@ -511,7 +511,7 @@ void reverse() {
 			            : index;
 			// This should have been enforced by the earlier checking.
 			assume(tileOfs < nbTiles + options.trim);
-			size_t palID = palmap ? (*palmap)[index] : attribute & 0b111;
+			size_t palID = (palmap ? (*palmap)[index] : attribute & 0b111) - options.basePalID;
 			assume(palID < palettes.size()); // Should be ensured on data read
 
 			// We do not have data for tiles trimmed with `-x`, so assume they are "blank"

test/gfx/base_ids.flags

@@ -0,0 +1,3 @@
+-b 15
+-l 3
+-m

test/gfx/base_ids.out.attrmap

@@ -0,0 +1 @@
+

test/gfx/base_ids.out.tilemap

@@ -0,0 +1 @@
+