spr center flag

2 files changed, 11 insertions, 3 deletions

diff --git a/src/px.c b/src/px.c
index 5281432..d7c8650 100644
--- a/src/px.c
+++ b/src/px.c
@@ -220,10 +220,17 @@ _pxSpr(const PxSprArgs *args)
 	int h = (args->h < 0) ? (int)(args->spr->h) : (args->h);
 	h = pxMin(h, args->spr->h - args->iy);
 
+	int ox = args->x;
+	int oy = args->y;
+	if (args->center) {
+		ox -= w / 2;
+		oy -= h / 2;
+	}
+
 	for (int y = 0; y < h; y++) {
 		for (int x = 0; x < w; x++) {
-			const int dx = x + args->x;
-			const int dy = y + args->y;
+			const int dx = x + ox;
+			const int dy = y + oy;
 			int ix = args->ix + ((args->flip_x)
 			                     ? (w - x - 1)
 			                     : (x));
diff --git a/src/px.h b/src/px.h
index 1d08bd1..3d0db03 100644
--- a/src/px.h
+++ b/src/px.h
@@ -34,6 +34,7 @@ typedef struct {
 	int h;
 	bool flip_x;
 	bool flip_y;
+	bool center;
 } PxSprArgs;
 
 typedef struct {
@@ -94,7 +95,7 @@ void pxLine(int x0, int y0, int x1, int y1, PxCol col);
 /* Draw sprite. */
 #define pxSpr(...) _pxSpr(&(const PxSprArgs){ \
 	.x=0, .y=0, .ix=0, .iy=0, .w=-1, .h=-1, .flip_x=false, .flip_x=false, \
-	._=0, __VA_ARGS__})
+	.center=false, ._=0, __VA_ARGS__})
 void _pxSpr(const PxSprArgs *args);
 
 /* Bind palette index to new color. */