On 8 September 2017 at 16:11, Nikolay Sivov nsivov@codeweavers.com wrote:
+static BOOL d2d_point_on_segment(const D2D1_POINT_2F *q, const D2D1_POINT_2F *p0,
const D2D1_POINT_2F *p1, float tolerance)+{
- float dot, edge_length, distance;
- D2D1_POINT_2F v_p, v_q, n;
- d2d_point_subtract(&v_p, p1, p0);
- if ((edge_length = d2d_point_length(&v_p)) == 0.0f)
return FALSE;- /* Edge distance. */
- d2d_point_subtract(&v_q, q, p0);
- n.x = -v_p.y;
- n.y = v_p.x;
Unfortunately it's not that easy when "transform" is a world transformation instead of a geometry transformation. I.e., when you have for example a shear transformation, the "normal" is no longer necessarily perpendicular to the line segment. Put a different way, you're potentially testing against a parallelogram instead of a rectangle. In a sense you account for that with stroke_widths[], but see below.
- distance = fabsf(d2d_point_dot(&v_q, &n)) / edge_length;
- if (distance >= tolerance)
return FALSE;- /* Test if normal and edge intersect. */
- dot = d2d_point_dot(&v_q, &v_p);
- return dot >= 0.0f && dot <= edge_length * edge_length;
+}
Likewise, this doesn't do the right thing under all transformations.
d2d_point_transform(&v_s[0], transform, stroke_width, 0.0f);d2d_point_transform(&v_s[1], transform, stroke_width, 0.0f);d2d_point_transform(&origin, transform, 0.0f, 0.0f);d2d_point_subtract(&v_s[0], &v_s[0], &origin);d2d_point_subtract(&v_s[1], &v_s[1], &origin);stroke_widths[0] = d2d_point_length(&v_s[0]);stroke_widths[1] = d2d_point_length(&v_s[1]);
This ends up with the same value for stroke_widths[0] and stroke_widths[1].
d2d_point_subtract(&v, &point, &vertices[i]);if (d2d_point_dot(&v, &v) < tolerance * tolerance){*contains = TRUE;break;}
This tests around the corner of the joins, but note that there's potentially a space between that corner and the start of the line segment that this would miss.
- else
- {
D2D1_POINT_2F d, s;s.x = rect->right - rect->left;s.y = rect->bottom - rect->top;d.x = fabsf((rect->right + rect->left) * 0.5f - point.x);d.y = fabsf((rect->bottom + rect->top) * 0.5f - point.y);/* Inside test. */if (d.x <= (s.x - stroke_width) * 0.5f - tolerance && d.y <= (s.y - stroke_width) * 0.5f - tolerance){*contains = FALSE;return S_OK;}if (tolerance == 0.0f){*contains = d.x < (s.x + stroke_width) * 0.5f && d.y < (s.y + stroke_width) * 0.5f;}else{d.x = max(d.x - (s.x + stroke_width) * 0.5f, 0.0f);d.y = max(d.y - (s.y + stroke_width) * 0.5f, 0.0f);*contains = d2d_point_dot(&d, &d) < tolerance * tolerance;}- }
Ultimately it's not that important, but I think there's something to be said for handling the "!transform" case first as a special case. I.e.,
if (!transform) { ... return S_OK; }
/* General case. */
diff --git a/dlls/d2d1/tests/d2d1.c b/dlls/d2d1/tests/d2d1.c index f6261295b6..95a010b13e 100644 --- a/dlls/d2d1/tests/d2d1.c +++ b/dlls/d2d1/tests/d2d1.c @@ -76,6 +76,15 @@ struct expected_geometry_figure const struct geometry_segment *segments; };
+struct contains_point_test +{
- D2D1_MATRIX_3X2_F transform;
- D2D1_POINT_2F point;
- float tolerance;
- float stroke_width;
- BOOL contains;
+};
Unless these are reused between tests, we tend to keep them local to the function.
- static const struct contains_point_test stroke_contains[] =
- {
{{0.0f, 0.0f, 0.0f, 1.0f}, {0.1f, 10.0f}, 0.0f, 1.0f, FALSE},{{0.0f, 0.0f, 0.0f, 1.0f}, {5.0f, 10.0f}, 5.0f, 1.0f, FALSE},{{0.0f, 0.0f, 0.0f, 1.0f}, {4.9f, 10.0f}, 5.0f, 1.0f, TRUE},{{0.0f, 0.0f, 0.0f, 1.0f}, {5.0f, 10.0f}, -5.0f, 1.0f, FALSE},{{0.0f, 0.0f, 0.0f, 1.0f}, {4.9f, 10.0f}, -5.0f, 1.0f, TRUE},{{1.0f, 0.0f, 0.0f, 1.0f}, {0.0f, 10.0f}, 0.0f, 1.0f, TRUE},{{1.0f, 0.0f, 0.0f, 1.0f}, {0.1f, 10.0f}, 0.0f, 1.0f, TRUE},{{1.0f, 0.0f, 0.0f, 1.0f}, {0.5f, 10.0f}, 0.0f, 1.0f, FALSE},{{1.0f, 0.0f, 0.0f, 1.0f}, {0.0f, 10.0f}, 1.0f, 1.0f, TRUE},{{1.0f, 0.0f, 0.0f, 1.0f}, {0.59f, 10.0f}, 1.0f, 1.0f, TRUE},{{1.0f, 0.0f, 0.0f, 1.0f}, {-0.59f, 10.0f}, 1.0f, 1.0f, TRUE},{{1.0f, 0.0f, 0.0f, 1.0f}, {0.59f, 10.0f}, -1.0f, 1.0f, TRUE},{{1.0f, 0.0f, 0.0f, 1.0f}, {-0.59f, 10.0f}, -1.0f, 1.0f, TRUE},- };
Rotations and shears are interesting.
@@ -2766,6 +2793,108 @@ static void test_rectangle_geometry(void) ok(SUCCEEDED(hr), "FillContainsPoint() failed, hr %#x.\n", hr); ok(!!contains, "Got wrong hit test result %d.\n", contains);
- /* Stroked area hittesting. Edge. */
- contains = FALSE;
- set_point(&point, 0.4f, 10.0f);
- hr = ID2D1RectangleGeometry_StrokeContainsPoint(geometry, point, 1.0f, NULL, NULL, 0.0f, &contains);
- ok(SUCCEEDED(hr), "StrokeContainsPoint() failed, hr %#x.\n", hr);
- ok(!!contains, "Got wrong hit test result %d.\n", contains);
We tend to use %#x for BOOLs. And well, you might as well make these array based as well.