Implement TMX map loading

app/CMakeLists.txt

@@ -5,4 +5,4 @@ set_default_target_options(game)
 target_include_directories(game PUBLIC include)
 
 target_link_libraries(game
-  PRIVATE SDL2::SDL2 SDL2::SDL2main)
+  PRIVATE LibXml2::LibXml2 SDL2::SDL2 SDL2::SDL2main)

app/main.c

@@ -5,16 +5,32 @@
 
 #include <SDL2/SDL.h>
 #include <assert.h>
+#include <ctype.h>
+#include <libxml/parser.h>
 
 #define TILESIZE 32
 #define WINWIDTH 30
 #define WINHEIGHT 20
 
-SDL_Window *window;
-SDL_Renderer *renderer;
+#define MAX_PATH_LEN 128
 
-int main(void)
+#define MAP_ASSET "/map.tmx"
+#define MAPWIDTH 112
+#define MAPHEIGHT 112
+#define MAPSHIFTX 48
+#define MAPSHIFTY 48
+
+static SDL_Window *window;
+static SDL_Renderer *renderer;
+static unsigned map[MAPWIDTH][MAPHEIGHT];
+
+int main(int argc, char *argv[])
 {
+	if (2 != argc) {
+		fprintf(stderr, "Usage: %s ASSETS-DIR\n", argv[0]);
+		return 1;
+	}
+
 	int err = SDL_Init(SDL_INIT_VIDEO);
 	assert(0 == err);
 	window = SDL_CreateWindow(
@@ -24,6 +40,75 @@ int main(void)
 	renderer = SDL_CreateRenderer(window, -1, 0);
 	assert(NULL != renderer);
 
+	xmlDocPtr doc;
+	xmlNodePtr node;
+	char mappath[MAX_PATH_LEN];
+	strncpy(mappath, argv[1], MAX_PATH_LEN);
+	strncat(mappath, MAP_ASSET, MAX_PATH_LEN);
+	doc = xmlParseFile(mappath);
+	assert(NULL != doc);
+	node = xmlDocGetRootElement(doc);
+	assert(0 == xmlStrcmp(node->name, (const xmlChar *)"map"));
+	node = node->xmlChildrenNode;
+	while (NULL != node
+	       && xmlStrcmp(node->name, (const xmlChar *)"layer") != 0)
+		node = node->next;
+	assert(NULL != node);
+	node = node->xmlChildrenNode;
+	while (NULL != node
+	       && xmlStrcmp(node->name, (const xmlChar *)"data") != 0)
+		node = node->next;
+	assert(NULL != node);
+
+	xmlNodePtr chunk_contents;
+	for (node = node->xmlChildrenNode; NULL != node; node = node->next) {
+		if (0 != xmlStrcmp(node->name, (const xmlChar *)"chunk"))
+			continue;
+
+		xmlChar *x_attr, *y_attr;
+		x_attr = xmlGetProp(node, (const xmlChar *)"x");
+		y_attr = xmlGetProp(node, (const xmlChar *)"y");
+		const int chunk_x = atoi((const char *)x_attr);
+		const int chunk_y = atoi((const char *)y_attr);
+
+		chunk_contents = node->xmlChildrenNode;
+		assert(
+		    0 == xmlStrcmp(chunk_contents->name, (const xmlChar *)"text"));
+		int x = chunk_x + MAPSHIFTX, y = chunk_y + MAPSHIFTY;
+		xmlChar buf[10];
+		const xmlChar *p, *q;
+		q = chunk_contents->content;
+		while (isspace((const char)*q))
+			++q;
+		p = q;
+		while ('\0' != *q) {
+			switch (*q) {
+			case (xmlChar)',':
+				memset(buf, 0, sizeof(buf));
+				memcpy(buf, p, sizeof(xmlChar) * (q - p));
+				assert(x < MAPWIDTH && y < MAPHEIGHT);
+				map[x][y] = (unsigned)atoi((const char *)buf);
+				++x;
+				p = ++q;
+				break;
+			case (xmlChar)'\n':
+				if (x < MAPWIDTH) {
+					memset(buf, 0, sizeof(buf));
+					memcpy(buf, p, sizeof(xmlChar) * (q - p));
+					assert(y < MAPHEIGHT);
+					map[x][y] = (unsigned)atoi((const char *)buf);
+				}
+				x = chunk_x + MAPSHIFTX;
+				++y;
+				p = ++q;
+				break;
+			default:
+				++q;
+				break;
+			}
+		}
+	}
+
 	SDL_Event event;
 	SDL_RenderClear(renderer);
 	while (1) {