Adapt heightForWidth from Qt for text wrapping

src/immdraw.h

@@ -15,7 +15,7 @@ static inline void immdraw_fill_rect(int16_t x, int16_t y, int16_t w, int16_t h,
 
 static inline void immdraw_font_draw(struct k3Font *font, int16_t x, int16_t y, int16_t w, float sz, size_t len, const char *txt, int alignment, float r, float g, float b, float a) {
 	struct k3RectF txtsz;
-	k3FontSz(font, sz, txt, &txtsz);
+	k3FontSz(font, sz, txt, w, &txtsz);
 	
 	if(alignment != k3M_ALIGN_LEFT) {
 		if(alignment == k3M_ALIGN_CENTER) {
@@ -25,11 +25,11 @@ static inline void immdraw_font_draw(struct k3Font *font, int16_t x, int16_t y,
 		}
 	}
 	
-	k3FontDraw(font, x, GameWndH - y - sz, sz, txt, (vec4) {r, g, b, a});
+	k3FontDraw(font, x, GameWndH - y - sz, sz, txt, w, (vec4) {r, g, b, a});
 }
-static inline void immdraw_font_size(struct k3Font *font, float sz, const char *txt, int16_t aabb[2]) {
+static inline void immdraw_font_size(struct k3Font *font, float sz, const char *txt, int16_t wall, int16_t aabb[2]) {
 	struct k3RectF txtsz;
-	k3FontSz(font, sz, txt, &txtsz);
+	k3FontSz(font, sz, txt, wall, &txtsz);
 	
 	aabb[0] = ceilf(txtsz.w);
 	aabb[1] = ceilf(txtsz.h);

src/k3font.c

@@ -97,7 +97,13 @@ static uint32_t read_utf8(const char **txt_) {
 	}
 }
 
-void k3FontSz(struct k3Font *this, float sz, const char *txt, struct k3RectF *ret) {
+void k3FontSz(struct k3Font *this, float sz, const char *txt, float wall, struct k3RectF *ret) {
+	if(wall < 0) {
+		wall = HUGE_VALF;
+	}
+	
+	float maxX = 0;
+	
 	float x = 0, y = sz;
 	while(1) {
 		uint32_t cp = read_utf8(&txt);
@@ -113,12 +119,23 @@ void k3FontSz(struct k3Font *this, float sz, const char *txt, struct k3RectF *re
 		
 		if(!g) continue;
 		
-		x += g->xadvance * this->lineScale * sz;
+		if(x + g->width > wall) {
+			x = 0;
+			y += sz;
 		}
-	ret->w = x;
+		
+		x += g->xadvance * this->lineScale * sz;
+		maxX = fmaxf(maxX, x);
+	}
+	
+	ret->w = maxX;
 	ret->h = y;
 }
-void k3FontDraw(struct k3Font *this, float xStart, float yStart, float sz, const char *txt, vec4 color) {
+void k3FontDraw(struct k3Font *this, float xStart, float yStart, float sz, const char *txt, float wall, vec4 color) {
+	if(wall < 0) {
+		wall = HUGE_VALF;
+	}
+	
 	float x = xStart, y = yStart;
 	while(1) {
 		uint32_t cp = read_utf8(&txt);
@@ -134,6 +151,11 @@ void k3FontDraw(struct k3Font *this, float xStart, float yStart, float sz, const
 		
 		if(!g) continue;
 		
+		if(x + g->width - xStart > wall) {
+			x = xStart;
+			y -= sz;
+		}
+		
 		struct k3Tex *tex = this->pages[g->page];
 		size_t texW = this->texW;
 		size_t texH = this->texH;

src/k3font.h

@@ -38,8 +38,8 @@ typedef struct k3Tex*(*k3FontTexLoader)(struct k3Font*, const char *name);
 struct k3Font *k3FontCreate();
 int k3FontLoad(struct k3Font*, const uint8_t *buf, size_t len, k3FontTexLoader);
 
-void k3FontSz(struct k3Font*, float sz, const char *txt, struct k3RectF *ret);
+void k3FontSz(struct k3Font*, float sz, const char *txt, float wall, struct k3RectF *ret);
-void k3FontDraw(struct k3Font*, float x, float y, float sz, const char *txt, vec4 color);
+void k3FontDraw(struct k3Font*, float x, float y, float sz, const char *txt, float wall, vec4 color);
 
 struct k3FontGlyph *k3FontGetGlyph(struct k3Font*, uint32_t cp);
 

src/k3menu.c

@@ -87,8 +87,11 @@ static bool linear_arrange(struct k3MEvent *ev, uint8_t *ud) {
 		c->x = o->x + padding[3];
 		c->y = y;
 		
-		c->w = c->wDesired - padding[1] - padding[3];
+		c->w = o->w - padding[1] - padding[3];
+		
+		if(!k3MEventSend(&(struct k3MEvent) {.original = o, .target = c, .code = k3M_EVENT_SET_HEIGHT_FROM_WIDTH})) {
 			c->h = c->hDesired;
+		}
 		
 		y += c->h;
 	}
@@ -225,7 +228,16 @@ static bool label_draw(struct k3MEvent *ev, uint8_t *ud) {
 	
 	return false;
 }
+static bool label_set_height_from_width(struct k3MEvent *ev, uint8_t *ud) {
+	struct k3MLabel *this = (void*) ev->target;
 	
+	int16_t pxsz[2];
+	immdraw_font_size(this->font, this->sz, this->txt, this->w, pxsz);
+	
+	this->h = pxsz[1];
+	
+	return true;
+}
 struct k3MLabel *k3MLabel(struct k3Font *font, float sz, const char *txt) {
 	struct k3MLabel *ret = calloc(1, sizeof(*ret));
 	ret->font = font;
@@ -233,11 +245,12 @@ struct k3MLabel *k3MLabel(struct k3Font *font, float sz, const char *txt) {
 	ret->txt = strdup(txt);
 	
 	k3MRegisterEventHandler(ret, k3M_EVENT_DRAW, label_draw, NULL, 0);
+	k3MRegisterEventHandler(ret, k3M_EVENT_SET_HEIGHT_FROM_WIDTH, label_set_height_from_width, NULL, 0);
 	
-	int16_t lblsz[2];
+	//int16_t lblsz[2];
-	immdraw_font_size(font, sz, txt, lblsz);
+	//immdraw_font_size(font, sz, txt, lblsz);
-	ret->w = lblsz[0];
+	//ret->w = lblsz[0];
-	ret->h = lblsz[1];
+	//ret->h = lblsz[1];
 	
 	return ret;
 }

src/k3menu.h

@@ -22,7 +22,8 @@ struct k3MObj;
 #define k3M_EVENT_MEASURE 11
 #define k3M_EVENT_ARRANGE 12
 #define k3M_EVENT_POST_ARRANGE 13
-#define k3M_EVENT_ALL 14
+#define k3M_EVENT_SET_HEIGHT_FROM_WIDTH 14
+#define k3M_EVENT_ALL 15
 
 #define k3M_MOUSE_BUTTON_0 0
 #define k3M_MOUSE_BUTTON_1 1