Fix T53074: Use the pybuffer->itemsize to get the corresponding GLtype

It seems that `typestr` does not always define the final size of the element. And it varies by operating system.

Then use the `typestr` only to know the itemtype is `float` type or not.

1 files changed, 11 insertions, 16 deletions

diff --git a/source/blender/python/generic/bgl.c b/source/blender/python/generic/bgl.c
index a0185b0f4fa..072021c6ac9 100644
--- a/source/blender/python/generic/bgl.c
+++ b/source/blender/python/generic/bgl.c
@@ -472,34 +472,29 @@ int BGL_typeSize(int type)
 	return -1;
 }
 
-static int gl_buffer_type_from_py_format_char(char *typestr)
+static int gl_buffer_type_from_py_buffer(Py_buffer *pybuffer)
 {
+	char *typestr = pybuffer->format;
+	Py_ssize_t itemsize = pybuffer->itemsize;
+
 	if (ELEM(typestr[0], '<', '>', '|')) {
 		typestr += 1;
 	}
-	char format = typestr[0];
-	char byte_num = typestr[1];
 
-	switch (format) {
+	switch (typestr[0]) {
 		case 't':
 		case 'b':
 		case 'h':
-			if (!byte_num) return GL_BYTE;
-			ATTR_FALLTHROUGH;
 		case 'i':
-			if (!byte_num) return GL_SHORT;
-			ATTR_FALLTHROUGH;
 		case 'l':
-			if (!byte_num || byte_num == '4') return GL_INT;
-			if (byte_num == '1') return GL_BYTE;
-			if (byte_num == '2') return GL_SHORT;
+			if (itemsize == 1) return GL_BYTE;
+			if (itemsize == 2) return GL_SHORT;
+			if (itemsize == 4) return GL_INT;
 			break;
 		case 'f':
-			if (!byte_num) return GL_FLOAT;
-			ATTR_FALLTHROUGH;
 		case 'd':
-			if (!byte_num || byte_num == '8') return GL_DOUBLE;
-			if (byte_num == '4') return GL_FLOAT;
+			if (itemsize == 4) return GL_FLOAT;
+			if (itemsize == 8) return GL_DOUBLE;
 			break;
 	}
 	return -1; /* UNKNOWN */
@@ -797,7 +792,7 @@ static PyObject *Buffer_new(PyTypeObject *UNUSED(type), PyObject *args, PyObject
 			return NULL;
 		}
 
-		if (type != gl_buffer_type_from_py_format_char(pybuffer.format)) {
+		if (type != gl_buffer_type_from_py_buffer(&pybuffer)) {
 			PyErr_Format(PyExc_TypeError,
 			             "`GL_TYPE` and `typestr` of object with buffer interface do not match. '%s'", pybuffer.format);
 		}