diff options
Diffstat (limited to 'pixman/pixman/pixman-trap.c')
| -rw-r--r-- | pixman/pixman/pixman-trap.c | 132 |
1 files changed, 86 insertions, 46 deletions
diff --git a/pixman/pixman/pixman-trap.c b/pixman/pixman/pixman-trap.c index 35128ee3d..ab5c8c895 100644 --- a/pixman/pixman/pixman-trap.c +++ b/pixman/pixman/pixman-trap.c @@ -387,18 +387,95 @@ pixman_rasterize_trapezoid (pixman_image_t * image, } } +static const pixman_bool_t zero_src_has_no_effect[PIXMAN_N_OPERATORS] = +{ + FALSE, /* Clear 0 0 */ + FALSE, /* Src 1 0 */ + TRUE, /* Dst 0 1 */ + TRUE, /* Over 1 1-Aa */ + TRUE, /* OverReverse 1-Ab 1 */ + FALSE, /* In Ab 0 */ + FALSE, /* InReverse 0 Aa */ + FALSE, /* Out 1-Ab 0 */ + TRUE, /* OutReverse 0 1-Aa */ + TRUE, /* Atop Ab 1-Aa */ + FALSE, /* AtopReverse 1-Ab Aa */ + TRUE, /* Xor 1-Ab 1-Aa */ + TRUE, /* Add 1 1 */ +}; + +static pixman_bool_t +get_trap_extents (pixman_op_t op, pixman_image_t *dest, + const pixman_trapezoid_t *traps, int n_traps, + pixman_box32_t *box) +{ + int i; + + /* When the operator is such that a zero source has an + * effect on the underlying image, we have to + * composite across the entire destination + */ + if (!zero_src_has_no_effect [op]) + { + box->x1 = 0; + box->y1 = 0; + box->x2 = dest->bits.width; + box->y2 = dest->bits.height; + return TRUE; + } + + box->x1 = INT32_MAX; + box->y1 = INT32_MAX; + box->x2 = INT32_MIN; + box->y2 = INT32_MIN; + + for (i = 0; i < n_traps; ++i) + { + const pixman_trapezoid_t *trap = &(traps[i]); + int y1, y2; + + if (!pixman_trapezoid_valid (trap)) + continue; + + y1 = pixman_fixed_to_int (trap->top); + if (y1 < box->y1) + box->y1 = y1; + + y2 = pixman_fixed_to_int (pixman_fixed_ceil (trap->bottom)); + if (y2 > box->y2) + box->y2 = y2; + +#define EXTEND_MIN(x) \ + if (pixman_fixed_to_int ((x)) < box->x1) \ + box->x1 = pixman_fixed_to_int ((x)); +#define EXTEND_MAX(x) \ + if (pixman_fixed_to_int (pixman_fixed_ceil ((x))) > box->x2) \ + box->x2 = pixman_fixed_to_int (pixman_fixed_ceil ((x))); + +#define EXTEND(x) \ + EXTEND_MIN(x); \ + EXTEND_MAX(x); + + EXTEND(trap->left.p1.x); + EXTEND(trap->left.p2.x); + EXTEND(trap->right.p1.x); + EXTEND(trap->right.p2.x); + } + + if (box->x1 >= box->x2 || box->y1 >= box->y2) + return FALSE; + + return TRUE; +} + /* * pixman_composite_trapezoids() * * All the trapezoids are conceptually rendered to an infinitely big image. * The (0, 0) coordinates of this image are then aligned with the (x, y) * coordinates of the source image, and then both images are aligned with - * the (x, y) coordinates of the destination. Then, in principle, compositing - * of these three images takes place across the entire destination. - * - * FIXME: However, there is currently a bug, where we restrict this compositing - * to the bounding box of the trapezoids. This is incorrect for operators such - * as SRC and IN where blank source pixels do have an effect on the destination. + * the (x, y) coordinates of the destination. Then these three images are + * composited across the entire destination. */ PIXMAN_EXPORT void pixman_composite_trapezoids (pixman_op_t op, @@ -439,46 +516,9 @@ pixman_composite_trapezoids (pixman_op_t op, { pixman_image_t *tmp; pixman_box32_t box; - - box.x1 = INT32_MAX; - box.y1 = INT32_MAX; - box.x2 = INT32_MIN; - box.y2 = INT32_MIN; - - for (i = 0; i < n_traps; ++i) - { - const pixman_trapezoid_t *trap = &(traps[i]); - int y1, y2; - - if (!pixman_trapezoid_valid (trap)) - continue; - - y1 = pixman_fixed_to_int (trap->top); - if (y1 < box.y1) - box.y1 = y1; - - y2 = pixman_fixed_to_int (pixman_fixed_ceil (trap->bottom)); - if (y2 > box.y2) - box.y2 = y2; - -#define EXTEND_MIN(x) \ - if (pixman_fixed_to_int ((x)) < box.x1) \ - box.x1 = pixman_fixed_to_int ((x)); -#define EXTEND_MAX(x) \ - if (pixman_fixed_to_int (pixman_fixed_ceil ((x))) > box.x2) \ - box.x2 = pixman_fixed_to_int (pixman_fixed_ceil ((x))); - -#define EXTEND(x) \ - EXTEND_MIN(x); \ - EXTEND_MAX(x); - - EXTEND(trap->left.p1.x); - EXTEND(trap->left.p2.x); - EXTEND(trap->right.p1.x); - EXTEND(trap->right.p2.x); - } - - if (box.x1 >= box.x2 || box.y1 >= box.y2) + int i; + + if (!get_trap_extents (op, dst, traps, n_traps, &box)) return; tmp = pixman_image_create_bits ( |