X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=src%2Fsp-item-transform.cpp;h=4caf155bfdad7ec4cb771e4e418dfbfb39264306;hb=8d358698ecbf192ba7c6dc05d4f7de7592753d9f;hp=d622112453a9b222ea4b610dd9ef382407d94cb5;hpb=ae186f970fdb7668d77390504ba9ad752addac8e;p=inkscape.git diff --git a/src/sp-item-transform.cpp b/src/sp-item-transform.cpp index d62211245..4caf155bf 100644 --- a/src/sp-item-transform.cpp +++ b/src/sp-item-transform.cpp @@ -33,7 +33,7 @@ sp_item_rotate_rel(SPItem *item, NR::rotate const &rotation) NR::Matrix affine = NR::Matrix(inverse(s)) * NR::Matrix(rotation) * NR::Matrix(s); // Rotate item. - sp_item_set_i2d_affine(item, sp_item_i2d_affine(item) * affine); + sp_item_set_i2d_affine(item, sp_item_i2d_affine(item) * to_2geom(affine)); // Use each item's own transform writer, consistent with sp_selection_apply_affine() sp_item_write_transform(item, SP_OBJECT_REPR(item), item->transform); @@ -46,11 +46,12 @@ sp_item_rotate_rel(SPItem *item, NR::rotate const &rotation) void sp_item_scale_rel (SPItem *item, NR::scale const &scale) { - NR::translate const s(sp_item_bbox_desktop(item).midpoint()); // use getCenter? - - sp_item_set_i2d_affine(item, - sp_item_i2d_affine(item) * inverse(s) * scale * s); - sp_item_write_transform(item, SP_OBJECT_REPR(item), item->transform); + NR::Maybe bbox = sp_item_bbox_desktop(item); + if (bbox) { + NR::translate const s(bbox->midpoint()); // use getCenter? + sp_item_set_i2d_affine(item, sp_item_i2d_affine(item) * to_2geom(NR::Matrix(inverse(s)) * scale * s)); + sp_item_write_transform(item, SP_OBJECT_REPR(item), item->transform); + } } void @@ -62,7 +63,7 @@ sp_item_skew_rel (SPItem *item, double skewX, double skewY) NR::Matrix const skew(1, skewY, skewX, 1, 0, 0); NR::Matrix affine = NR::Matrix(inverse(s)) * skew * NR::Matrix(s); - sp_item_set_i2d_affine(item, sp_item_i2d_affine(item) * affine); + sp_item_set_i2d_affine(item, sp_item_i2d_affine(item) * to_2geom(affine)); sp_item_write_transform(item, SP_OBJECT_REPR(item), item->transform); // Restore the center position (it's changed because the bbox center changed) @@ -73,14 +74,14 @@ sp_item_skew_rel (SPItem *item, double skewX, double skewY) void sp_item_move_rel(SPItem *item, NR::translate const &tr) { - sp_item_set_i2d_affine(item, sp_item_i2d_affine(item) * tr); + sp_item_set_i2d_affine(item, sp_item_i2d_affine(item) * to_2geom(tr)); sp_item_write_transform(item, SP_OBJECT_REPR(item), item->transform); } /* -** Returns the matrix you need to apply to an object with given bbox and strokewidth to -scale/move it to the new box x0/y0/x1/y1. Takes into account the "scale stroke" +** Returns the matrix you need to apply to an object with given visual bbox and strokewidth to +scale/move it to the new visual bbox x0/y0/x1/y1. Takes into account the "scale stroke" preference value passed to it. Has to solve a quadratic equation to make sure the goal is met exactly and the stroke scaling is obeyed. */ @@ -96,13 +97,13 @@ get_scale_transform_with_stroke (NR::Rect &bbox_param, gdouble strokewidth, bool NR::Matrix scale = NR::Matrix (NR::scale (1, 1)); // scale component NR::Matrix unbudge = NR::Matrix (NR::translate (0, 0)); // move component to compensate for the drift caused by stroke width change - gdouble w0 = bbox.extent(NR::X); + gdouble w0 = bbox.extent(NR::X); // will return a value >= 0, as required further down the road gdouble h0 = bbox.extent(NR::Y); - gdouble w1 = x1 - x0; + gdouble w1 = x1 - x0; // can have any sign gdouble h1 = y1 - y0; gdouble r0 = strokewidth; - if (bbox.isEmpty() || bbox.extent(NR::X) < 1e-06 || bbox.extent(NR::Y) < 1e-06) { + if (bbox.isEmpty()) { NR::Matrix move = NR::Matrix(NR::translate(x0 - bbox.min()[NR::X], y0 - bbox.min()[NR::Y])); return (move); // cannot scale from empty boxes at all, so only translate } @@ -113,25 +114,42 @@ get_scale_transform_with_stroke (NR::Rect &bbox_param, gdouble strokewidth, bool return (p2o * direct * o2n); // can't solve the equation: one of the dimensions is equal to stroke width, so return the straightforward scaler } + int flip_x = (w1 > 0) ? 1 : -1; + int flip_y = (h1 > 0) ? 1 : -1; + + // w1 and h1 will be negative when mirroring, but if so then e.g. w1-r0 won't make sense + // Therefore we will use the absolute values from this point on + w1 = fabs(w1); + h1 = fabs(h1); + r0 = fabs(r0); + // w0 and h0 will always be positive due to the definition extent() + gdouble ratio_x = (w1 - r0) / (w0 - r0); gdouble ratio_y = (h1 - r0) / (h0 - r0); - NR::Matrix direct_constant_r = NR::Matrix (NR::scale(ratio_x, ratio_y)); + + NR::Matrix direct_constant_r = NR::Matrix (NR::scale(flip_x * ratio_x, flip_y * ratio_y)); if (transform_stroke && r0 != 0 && r0 != NR_HUGE) { // there's stroke, and we need to scale it // These coefficients are obtained from the assumption that scaling applies to the // non-stroked "shape proper" and that stroke scale is scaled by the expansion of that - // matrix - gdouble A = -(w0 *h0) + r0*(w0 + h0); + // matrix. We're trying to solve this equation: + // r1 = r0 * sqrt (((w1-r0)/(w0-r0))*((h1-r0)/(h0-r0))) + // The operant of the sqrt() must be positive, which is ensured by the fabs() a few lines above + gdouble A = -w0*h0 + r0*(w0 + h0); gdouble B = -(w1 + h1) * r0*r0; gdouble C = w1 * h1 * r0*r0; if (B*B - 4*A*C > 0) { - gdouble r1 = (-B - sqrt (B*B - 4*A*C))/(2*A); + gdouble r1 = fabs((-B - sqrt(B*B - 4*A*C))/(2*A)); //gdouble r2 = (-B + sqrt (B*B - 4*A*C))/(2*A); //std::cout << "r0" << r0 << " r1" << r1 << " r2" << r2 << "\n"; + // + // If w1 < 0 then the scale will be wrong if we just do + // gdouble scale_x = (w1 - r1)/(w0 - r0); + // Here we also need the absolute values of w0, w1, h0, h1, and r1 gdouble scale_x = (w1 - r1)/(w0 - r0); gdouble scale_y = (h1 - r1)/(h0 - r0); - scale *= NR::scale(scale_x, scale_y); - unbudge *= NR::translate (-0.5 * (r0 * scale_x - r1), -0.5 * (r0 * scale_y - r1)); + scale *= NR::scale(flip_x * scale_x, flip_y * scale_y); + unbudge *= NR::translate (-flip_x * 0.5 * (r0 * scale_x - r1), -flip_y * 0.5 * (r0 * scale_y - r1)); } else { scale *= direct; } @@ -140,13 +158,45 @@ get_scale_transform_with_stroke (NR::Rect &bbox_param, gdouble strokewidth, bool scale *= direct; } else {// nonscaling strokewidth scale *= direct_constant_r; - unbudge *= NR::translate (0.5 * r0 * (1 - ratio_x), 0.5 * r0 * (1 - ratio_y)); + unbudge *= NR::translate (flip_x * 0.5 * r0 * (1 - ratio_x), flip_y * 0.5 * r0 * (1 - ratio_y)); } } return (p2o * scale * unbudge * o2n); } +NR::Rect +get_visual_bbox (NR::Maybe const &initial_geom_bbox, NR::Matrix const &abs_affine, gdouble const initial_strokewidth, bool const transform_stroke) +{ + + g_assert(initial_geom_bbox); + + // Find the new geometric bounding box; Do this by transforming each corner of + // the initial geometric bounding box individually and fitting a new boundingbox + // around the transformerd corners + NR::Point const p0 = initial_geom_bbox->corner(0) * abs_affine; + NR::Rect new_geom_bbox = NR::Rect(p0, p0); + for (unsigned i = 1 ; i < 4 ; i++) { + new_geom_bbox.expandTo(initial_geom_bbox->corner(i) * abs_affine); + } + + NR::Rect new_visual_bbox = new_geom_bbox; + if (initial_strokewidth > 0 && initial_strokewidth < NR_HUGE) { + if (transform_stroke) { + // scale stroke by: sqrt (((w1-r0)/(w0-r0))*((h1-r0)/(h0-r0))) (for visual bboxes, see get_scale_transform_with_stroke) + // equals scaling by: sqrt ((w1/w0)*(h1/h0)) for geometrical bboxes + // equals scaling by: sqrt (area1/area0) for geometrical bboxes + gdouble const new_strokewidth = initial_strokewidth * sqrt (new_geom_bbox.area() / initial_geom_bbox->area()); + new_visual_bbox.growBy(0.5 * new_strokewidth); + } else { + // Do not transform the stroke + new_visual_bbox.growBy(0.5 * initial_strokewidth); + } + } + + return new_visual_bbox; +} + /* Local Variables: mode:c++