[Git][freetype/freetype][bitmap_convert] * src/base/ftbitmap.c (FT_Bitmap_Copy): Clarify the flow control.

[Alexei Podtelezhnikov (@apodtele)]

Alexei Podtelezhnikov pushed to branch bitmap_convert at FreeType / FreeType

Commits:

• 468eaf19
  by Alexei Podtelezhnikov at 2022-09-21T16:57:34+00:00

  * src/base/ftbitmap.c (FT_Bitmap_Copy): Clarify the flow control.
  * include/freetype/ftbitmap.h (FT_Bitmap_Copy): Ditto.
  

2 changed files:

• include/freetype/ftbitmap.h
• src/base/ftbitmap.c

Changes:

include/freetype/ftbitmap.h

---

...	...	@@ -47,14 +47,6 @@ FT_BEGIN_HEADER
47	47	* @description:
48	48	* This section contains functions for handling @FT_Bitmap objects,
49	49	* automatically adjusting the target's bitmap buffer size as needed.
50		- *
51		- * Note that none of the functions changes the bitmap's 'flow' (as
52		- * indicated by the sign of the `pitch` field in @FT_Bitmap).
53		- *
54		- * To set the flow, assign an appropriate positive or negative value to
55		- * the `pitch` field of the target @FT_Bitmap object after calling
56		- * @FT_Bitmap_Init but before calling any of the other functions
57		- * described here.
58	50	*/
59	51
60	52
...	...	@@ -105,8 +97,14 @@ FT_BEGIN_HEADER
105	97	* FreeType error code. 0~means success.
106	98	*
107	99	* @note:
108		- * `source->buffer` and `target->buffer` must neither be equal nor
109		- * overlap.
	100	+ * This function reallocates the memory in the target bitmap, which has
	101	+ * to be valid, either initialized by @FT_Bitmap_Init or reused multiple
	102	+ * times. `source->buffer` and `target->buffer` must neither be equal
	103	+ * nor overlap. Use @FT_Bitmap_Done to finally remove the bitmap object.
	104	+ *
	105	+ * The source and target bitmaps can have different flows if their
	106	+ * pitches are set to opposite signs before calling this function.
	107	+ * Otherwise, the flow is preserved.
110	108	*/
111	109	FT_EXPORT( FT_Error )
112	110	FT_Bitmap_Copy( FT_Library library,

src/base/ftbitmap.c

---

...	...	@@ -67,8 +67,7 @@
67	67	FT_Memory memory;
68	68	FT_Error error = FT_Err_Ok;
69	69	FT_Int pitch;
70		-
71		- FT_Int source_pitch_sign, target_pitch_sign;
	70	+ FT_Int flip;
72	71
73	72
74	73	if ( !library )
...	...	@@ -80,15 +79,15 @@
80	79	if ( source == target )
81	80	return FT_Err_Ok;
82	81
83		- source_pitch_sign = source->pitch < 0 ? -1 : 1;
84		- target_pitch_sign = target->pitch < 0 ? -1 : 1;
	82	+ flip = ( source->pitch < 0 && target->pitch > 0 ) ||
	83	+ ( source->pitch > 0 && target->pitch < 0 );
85	84
86	85	memory = library->memory;
87	86	FT_FREE( target->buffer );
88	87
89	88	*target = *source;
90	89
91		- if ( source_pitch_sign != target_pitch_sign )
	90	+ if ( flip )
92	91	target->pitch = -target->pitch;
93	92
94	93	if ( !source->buffer )
...	...	@@ -102,10 +101,7 @@
102	101
103	102	if ( !error )
104	103	{
105		- if ( source_pitch_sign == target_pitch_sign )
106		- FT_MEM_COPY( target->buffer, source->buffer,
107		- (FT_Long)source->rows * pitch );
108		- else
	104	+ if ( flip )
109	105	{
110	106	/* take care of bitmap flow */
111	107	FT_UInt i;
...	...	@@ -123,6 +119,9 @@
123	119	t -= pitch;
124	120	}
125	121	}
	122	+ else
	123	+ FT_MEM_COPY( target->buffer, source->buffer,
	124	+ (FT_Long)source->rows * pitch );
126	125	}
127	126
128	127	return error;

—
View it on GitLab.
You're receiving this email because of your account on gitlab.freedesktop.org. Manage all notifications · Help