diff options
Diffstat (limited to 'libgnomecanvas/gnome-canvas.c')
| -rw-r--r-- | libgnomecanvas/gnome-canvas.c | 90 |
1 files changed, 86 insertions, 4 deletions
diff --git a/libgnomecanvas/gnome-canvas.c b/libgnomecanvas/gnome-canvas.c index 958fc45e1c..203f36d909 100644 --- a/libgnomecanvas/gnome-canvas.c +++ b/libgnomecanvas/gnome-canvas.c @@ -1044,6 +1044,44 @@ gnome_canvas_item_i2w_affine (GnomeCanvasItem *item, gdouble affine[6]) } } +void +gnome_canvas_item_i2w_matrix (GnomeCanvasItem *item, cairo_matrix_t *matrix) +{ + g_return_if_fail (GNOME_IS_CANVAS_ITEM (item)); + g_return_if_fail (matrix != NULL); + + cairo_matrix_init_identity (matrix); + + while (item) { + if (item->xform != NULL) { + cairo_matrix_t tmp; + gnome_canvas_matrix_from_affine (&tmp, item->xform); + cairo_matrix_multiply (matrix, matrix, &tmp); + } + + item = item->parent; + } +} + +void +gnome_canvas_item_w2i_matrix (GnomeCanvasItem *item, cairo_matrix_t *matrix) +{ + g_return_if_fail (GNOME_IS_CANVAS_ITEM (item)); + g_return_if_fail (matrix != NULL); + + cairo_matrix_init_identity (matrix); + + while (item) { + if (item->xform != NULL) { + cairo_matrix_t tmp; + gnome_canvas_matrix_from_affine (&tmp, item->xform); + cairo_matrix_multiply (matrix, &tmp, matrix); + } + + item = item->parent; + } +} + /** * gnome_canvas_item_w2i: * @item: A canvas item. @@ -1128,11 +1166,11 @@ gnome_canvas_item_i2c_affine (GnomeCanvasItem *item, gdouble affine[6]) void gnome_canvas_item_i2c_matrix (GnomeCanvasItem *item, cairo_matrix_t *matrix) { - gdouble affine; - - gnome_canvas_item_i2c_affine (item, &affine); + cairo_matrix_t i2w, w2c; - gnome_canvas_matrix_from_affine (matrix, &affine); + gnome_canvas_item_i2w_matrix (item, &i2w); + gnome_canvas_w2c_matrix (item->canvas, &w2c); + cairo_matrix_multiply (matrix, &i2w, &w2c); } /* Returns whether the item is an inferior of or is equal to the parent. */ @@ -3841,6 +3879,50 @@ gnome_canvas_w2c_affine (GnomeCanvas *canvas, gdouble affine[6]) } /** + * gnome_canvas_w2c_matrix: + * @canvas: A canvas. + * @matrix: (out): matrix to initialize + * + * Gets the transformtion matrix that converts from world coordinates to canvas + * pixel coordinates. + **/ +void +gnome_canvas_w2c_matrix (GnomeCanvas *canvas, cairo_matrix_t *matrix) +{ + g_return_if_fail (GNOME_IS_CANVAS (canvas)); + g_return_if_fail (matrix != NULL); + + cairo_matrix_init_scale (matrix, + canvas->pixels_per_unit, + canvas->pixels_per_unit); + cairo_matrix_translate (matrix, + -canvas->scroll_x1, + -canvas->scroll_y1); +} + +/** + * gnome_canvas_c2w_matrix: + * @canvas: A canvas. + * @matrix: (out): matrix to initialize + * + * Gets the transformtion matrix that converts from canvas pixel coordinates to + * world coordinates. + **/ +void +gnome_canvas_c2w_matrix (GnomeCanvas *canvas, cairo_matrix_t *matrix) +{ + g_return_if_fail (GNOME_IS_CANVAS (canvas)); + g_return_if_fail (matrix != NULL); + + cairo_matrix_init_translate (matrix, + canvas->scroll_x1, + canvas->scroll_y1); + cairo_matrix_scale (matrix, + 1 / canvas->pixels_per_unit, + 1 / canvas->pixels_per_unit); +} + +/** * gnome_canvas_w2c: * @canvas: A canvas. * @wx: World X coordinate. |