CVSROOT: /cvsroot/gnash
Module name: gnash
Changes by: Udo Giacomozzi <udog> 07/11/05 14:55:02
Modified files:
. : ChangeLog
server/parser : shape_character_def.cpp
Log message:
server/parser/shape_character_def.cpp: Implement a new point_test
algorithm (disabled by default since it's subject to discussion)
CVSWeb URLs:
http://cvs.savannah.gnu.org/viewcvs/gnash/ChangeLog?cvsroot=gnash&r1=1.4768&r2=1.4769
http://cvs.savannah.gnu.org/viewcvs/gnash/server/parser/shape_character_def.cpp?cvsroot=gnash&r1=1.42&r2=1.43
Patches:
Index: ChangeLog
===================================================================
RCS file: /cvsroot/gnash/gnash/ChangeLog,v
retrieving revision 1.4768
retrieving revision 1.4769
diff -u -b -r1.4768 -r1.4769
--- ChangeLog 5 Nov 2007 10:00:09 -0000 1.4768
+++ ChangeLog 5 Nov 2007 14:55:01 -0000 1.4769
@@ -1,3 +1,8 @@
+2007-11-05 Udo Giacomozzi <[EMAIL PROTECTED]>
+
+ * server/parser/shape_character_def.cpp: Implement a new point_test
+ algorithm (disabled by default since it's subject to discussion)
+
2007-11-05 Bastiaan Jacques <[EMAIL PROTECTED]>
* backend/render_handler_agg.cpp: Use agg::renderer_mclip instead
Index: server/parser/shape_character_def.cpp
===================================================================
RCS file: /cvsroot/gnash/gnash/server/parser/shape_character_def.cpp,v
retrieving revision 1.42
retrieving revision 1.43
diff -u -b -r1.42 -r1.43
--- server/parser/shape_character_def.cpp 4 Nov 2007 23:12:56 -0000
1.42
+++ server/parser/shape_character_def.cpp 5 Nov 2007 14:55:02 -0000
1.43
@@ -17,7 +17,7 @@
// Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
//
-/* $Id: shape_character_def.cpp,v 1.42 2007/11/04 23:12:56 strk Exp $ */
+/* $Id: shape_character_def.cpp,v 1.43 2007/11/05 14:55:02 udog Exp $ */
// Based on the public domain shape.cpp of Thatcher Ulrich <[EMAIL PROTECTED]>
2003
@@ -36,6 +36,11 @@
#include <cfloat>
#include <algorithm>
+// Define the macro below to use the new (Udo's) point-in-shape algorithm
+// which should work perfectly for any shape but ignores strokes at the
+// moment.
+#define USE_NEW_POINT_TEST
+
// Define the macro below to always compute bounds for shape characters
// and compare them with the bounds encoded in the SWF
//#define GNASH_DEBUG_SHAPE_BOUNDS 1
@@ -716,6 +721,272 @@
}
+#ifdef USE_NEW_POINT_TEST
+
+// TODO: this should be moved to libgeometry or something
+int curve_x_crossings(float x0, float y0, float x1, float y1,
+ float cx, float cy, float y, float &cross1, float &cross2)
+ // Finds the quadratic bezier curve crossings with the line Y.
+ // The function can have zero, one or two solutions (cross1, cross2). The
+ // return value of the function is the number of solutions.
+ // x0, y0 = start point of the curve
+ // x1, y1 = end point of the curve (anchor, aka ax|ay)
+ // cx, cy = control point of the curve
+ // If there are two crossings, cross1 is the nearest to x0|y0 on the
curve.
+{
+ int count=0;
+
+ // check if any crossings possible
+ if ( ((y0 < y) && (y1 < y) && (cy < y))
+ || ((y0 > y) && (y1 > y) && (cy > y)) ) {
+ // all above or below -- no possibility of crossing
+ return 0;
+ }
+
+ // Quadratic bezier is:
+ //
+ // p = (1-t)^2 * a0 + 2t(1-t) * c + t^2 * a1
+ //
+ // We need to solve for x at y.
+
+ // Use the quadratic formula.
+
+ // Numerical Recipes suggests this variation:
+ // q = -0.5 [b +sgn(b) sqrt(b^2 - 4ac)]
+ // x1 = q/a; x2 = c/q;
+
+
+ float A = y1 + y0 - 2 * cy;
+ float B = 2 * (cy - y0);
+ float C = y0 - y;
+
+ float rad = B * B - 4 * A * C;
+
+ if (rad < 0) {
+ return 0;
+ } else {
+ float q;
+ float sqrt_rad = sqrtf(rad);
+ if (B < 0) {
+ q = -0.5f * (B - sqrt_rad);
+ } else {
+ q = -0.5f * (B + sqrt_rad);
+ }
+
+ // The old-school way.
+ // float t0 = (-B + sqrt_rad) / (2 * A);
+ // float t1 = (-B - sqrt_rad) / (2 * A);
+
+ if (q != 0) {
+ float t1 = C / q;
+ if (t1 >= 0 && t1 < 1) {
+ float x_at_t1 =
+ x0 + 2 * (cx - x0) * t1 + (x1 + x0 - 2 * cx) * t1 * t1;
+
+ count++;
+ assert(count==1);
+ cross1 = x_at_t1; // order is important!
+ }
+ }
+
+ if (A != 0) {
+ float t0 = q / A;
+ if (t0 >= 0 && t0 < 1) {
+ float x_at_t0 =
+ x0 + 2 * (cx - x0) * t0 + (x1 + x0 - 2 * cx) * t0 * t0;
+
+ count++;
+ if (count==2)
+ cross2 = x_at_t0; // order is important!
+ else
+ cross1 = x_at_t0;
+ }
+ }
+
+
+ }
+
+ return count;
+}
+
+
+
+bool shape_character_def::point_test_local(float x, float y)
+ // Return true if the specified point is on the interior of our shape.
+ // Incoming coords are local coords.
+{
+
+ bool result = false;
+ unsigned npaths = m_paths.size();
+ float last_crossing;
+ bool first = true;
+
+ // browse all paths...
+ for (unsigned pno=0; pno<npaths; pno++) {
+
+ const path& pth = m_paths[pno];
+ unsigned nedges = pth.m_edges.size();
+
+ float next_pen_x = pth.m_ax;
+ float next_pen_y = pth.m_ay;
+ float pen_x, pen_y;
+
+ if (pth.m_new_shape) {
+ // beginning new subshape. if the previous subshape found a hit, return
+ // immediately, otherwise process new subshape.
+
+ if (result)
+ return true;
+ result = false;
+ first = true;
+ }
+
+ // ...and edges
+ for (unsigned eno=0; eno<nedges; eno++) {
+
+ const edge& edg = pth.m_edges[eno];
+ int fill;
+
+ pen_x = next_pen_x;
+ pen_y = next_pen_y;
+
+ next_pen_x = edg.m_ax;
+ next_pen_y = edg.m_ay;
+
+ /*
+ printf("EDGE #%d #%d [ %d %d ] : %.2f / %.2f -> %.2f / %.2f\n", pno, eno,
+ pth.m_fill0, pth.m_fill1,
+ pen_x, pen_y,
+ edg.m_ax, edg.m_ay);
+ */
+
+
+ float cross_x;
+ int cross_dir; // +1 = downward, -1 = upward
+
+ if (edg.is_straight()) {
+
+ // ==> straight line case
+
+ // ignore horizontal lines
+ if (edg.m_ay == pen_y) // TODO: better check for small difference?
+ continue;
+
+ // does this line cross the Y coordinate?
+ if ( ((pen_y <= y) && (edg.m_ay >= y))
+ || ((pen_y >= y) && (edg.m_ay <= y)) ) {
+
+ // calculate X crossing
+ cross_x = pen_x + (edg.m_ax - pen_x) *
+ (y - pen_y) / (edg.m_ay - pen_y);
+
+ if (pen_y > edg.m_ay)
+ cross_dir = -1; // upward
+ else
+ cross_dir = +1; // downward
+
+ } else {
+
+ // no crossing, ignore edge..
+ continue;
+
+ }
+
+ } else {
+
+ // ==> curve case
+
+ float cross1, cross2;
+ int dir1, dir2;
+
+ int scount = curve_x_crossings(pen_x, pen_y, edg.m_ax, edg.m_ay,
+ edg.m_cx, edg.m_cy, y, cross1, cross2);
+
+ dir1 = pen_y > y ? -1 : +1;
+ dir2 = dir1 * (-1); // second crossing always in opposite dir.
+
+ /*
+ printf(" curve crosses at %d points\n", scount);
+
+ if (scount>0)
+ printf(" first crossing at %.2f / %.2f, dir %d\n", cross1, y,
dir1);
+
+ if (scount>1)
+ printf(" second crossing at %.2f / %.2f, dir %d\n", cross2, y,
dir2);
+ */
+
+ // ignore crossings on the right side
+ if ((scount>1) && (cross2 > x))
+ scount--;
+
+ if ((scount>0) && (cross1 > x)) {
+ cross1 = cross2;
+ dir1 = dir2;
+ scount--;
+ }
+
+ if (scount==0)
+ continue; // no crossing left
+
+ // still two crossings? take the nearest
+ if (scount==2) {
+ if (cross2 > cross1) {
+ cross_x = cross2;
+ cross_dir = dir2;
+ } else {
+ cross_x = cross1;
+ cross_dir = dir1;
+ }
+ } else {
+ cross_x = cross1;
+ cross_dir = dir1;
+ }
+
+ } // curve
+
+
+ // ==> we have now:
+ // - a valid cross_x, which is left to "x"
+ // - cross_dir tells the direction of the crossing
+ // (+1 = downward, -1 = upward)
+
+
+ //printf(" found a crossing at %.2f / %.2f, dir %d\n", cross_x, y,
cross_dir);
+
+ // we only want crossings at the left of the hit test point
+ if (cross_x > x)
+ continue;
+
+ // we are looking for the crossing with the largest X coordinate,
+ // skip others
+ if (!first && (cross_x <= last_crossing))
+ continue;
+
+ // ==> we found a valid crossing
+
+ last_crossing = cross_x;
+ first = false;
+
+ // choose the appropriate fill style index (we need the one
+ // in direction to the hit test point)
+ if (cross_dir < 0)
+ fill = pth.m_fill1; // upward -> right style
+ else
+ fill = pth.m_fill0; // downward -> left style
+
+ result = fill > 0; // current result until we find a better crossing
+
+
+ } // for edge
+
+ } // for path
+
+
+ return result;
+}
+
+#else // ifdef USE_NEW_POINT_TEST
+
bool shape_character_def::point_test_local(float x, float y)
// Return true if the specified point is on the interior of our shape.
// Incoming coords are local coords.
@@ -778,7 +1049,7 @@
}
return false;
}
-
+#endif
float shape_character_def::get_height_local() const
{
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