fix color32.alpha_blend

include/typings/vmath.pyi

@@ -216,7 +216,7 @@ class color32:
     def ansi_bg(self, text: str) -> str: ...
 
     @staticmethod
-    def alpha_blend(src: color32, dst: color32) -> color32: ...
+    def alpha_blend(src: color32, dst: color32 | None) -> color32: ...
 
 
 def rgb(r: int, g: int, b: int) -> color32: ...

src/modules/vmath.c

@@ -896,7 +896,7 @@ static bool color32_from_hex_STATIC(int argc, py_Ref argv) {
     c11_color32 color;
     int res;
     if(hex.size == 7) {
-        res = scanf(hex.data, "#%2hhx%2hhx%2hhx", &color.r, &color.g, &color.b);
+        res = sscanf(hex.data, "#%2hhx%2hhx%2hhx", &color.r, &color.g, &color.b);
         if(res != 3) return ValueError("invalid hex color format");
         color.a = 255;
     } else {
@@ -1071,6 +1071,12 @@ static bool vmath_rgba(int argc, py_Ref argv) {
 
 static bool color32_alpha_blend_STATIC(int argc, py_Ref argv) {
     PY_CHECK_ARGC(2);
+    if(!py_checktype(&argv[0], tp_color32)) return false;
+    if(py_isnone(&argv[1])) {
+        py_assign(py_retval(), &argv[0]);
+        return true;
+    }
+    if(!py_checktype(&argv[1], tp_color32)) return false;
     c11_color32 src = py_tocolor32(&argv[0]);
     c11_color32 dst = py_tocolor32(&argv[1]);
     float alpha = src.a / 255.0f;

tests/80_color32.py

@@ -12,6 +12,7 @@ assert a.with_a(255).a == 255 and a.with_a(255).g == a.g
 
 assert a.to_hex() == '#64c8ff78'
 assert color32.from_hex('#64c8ff78') == a
+assert color32.from_hex('#64c8ff') == a.with_a(255)
 
 assert rgb(100, 200, 255) != a
 assert rgba(100, 200, 255, 120 / 255) == a
@@ -30,4 +31,6 @@ assert a.to_vec3i() == vec3i(int(a.r * alpha), int(a.g * alpha), int(a.b * alpha
 
 c = rgb(100, 200, 255)
 assert c.ansi_fg('xxx') == '\x1b[38;2;100;200;255mxxx\x1b[0m'
-assert c.ansi_bg('xxx') == '\x1b[48;2;100;200;255mxxx\x1b[0m'
+assert c.ansi_bg('xxx') == '\x1b[48;2;100;200;255mxxx\x1b[0m'
+
+assert color32.alpha_blend(a, None) == a