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-rw-r--r--src/gallium/state_trackers/vega/stroker.c1349
1 files changed, 1349 insertions, 0 deletions
diff --git a/src/gallium/state_trackers/vega/stroker.c b/src/gallium/state_trackers/vega/stroker.c
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index 0000000000..1b92d2b5c6
--- /dev/null
+++ b/src/gallium/state_trackers/vega/stroker.c
@@ -0,0 +1,1349 @@
+/**************************************************************************
+ *
+ * Copyright 2009 VMware, Inc. All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
+ * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
+ * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ **************************************************************************/
+
+#include "stroker.h"
+
+#include "path.h"
+#include "vg_state.h"
+#include "util_array.h"
+#include "arc.h"
+#include "bezier.h"
+#include "matrix.h"
+#include "path_utils.h"
+#include "polygon.h"
+
+#include "math.h"
+
+#ifndef M_2PI
+#define M_2PI 6.28318530717958647692528676655900576
+#endif
+
+#define STROKE_SEGMENTS 0
+#define STROKE_DEBUG 0
+#define DEBUG_EMITS 0
+
+static const VGfloat curve_threshold = 0.25f;
+
+static const VGfloat zero_coords[] = {0.f, 0.f};
+
+enum intersection_type {
+ NoIntersections,
+ BoundedIntersection,
+ UnboundedIntersection,
+};
+
+enum line_join_mode {
+ FlatJoin,
+ SquareJoin,
+ MiterJoin,
+ RoundJoin,
+ RoundCap
+};
+
+struct stroke_iterator {
+ void (*next)(struct stroke_iterator *);
+ VGboolean (*has_next)(struct stroke_iterator *);
+
+ VGPathCommand (*current_command)(struct stroke_iterator *it);
+ void (*current_coords)(struct stroke_iterator *it, VGfloat *coords);
+
+ VGint position;
+ VGint coord_position;
+
+ const VGubyte *cmds;
+ const VGfloat *coords;
+ VGint num_commands;
+ VGint num_coords;
+
+ struct polygon *curve_poly;
+ VGint curve_index;
+};
+
+static VGPathCommand stroke_itr_command(struct stroke_iterator *itr)
+{
+ return itr->current_command(itr);
+}
+
+static void stroke_itr_coords(struct stroke_iterator *itr, VGfloat *coords)
+{
+ itr->current_coords(itr, coords);
+}
+
+static void stroke_fw_itr_coords(struct stroke_iterator *itr, VGfloat *coords)
+{
+ if (itr->position >= itr->num_commands)
+ return;
+ switch (stroke_itr_command(itr)) {
+ case VG_MOVE_TO_ABS:
+ coords[0] = itr->coords[itr->coord_position];
+ coords[1] = itr->coords[itr->coord_position + 1];
+ break;
+ case VG_LINE_TO_ABS:
+ coords[0] = itr->coords[itr->coord_position];
+ coords[1] = itr->coords[itr->coord_position + 1];
+ break;
+ case VG_CUBIC_TO_ABS:
+ coords[0] = itr->coords[itr->coord_position];
+ coords[1] = itr->coords[itr->coord_position + 1];
+ coords[2] = itr->coords[itr->coord_position + 2];
+ coords[3] = itr->coords[itr->coord_position + 3];
+ coords[4] = itr->coords[itr->coord_position + 4];
+ coords[5] = itr->coords[itr->coord_position + 5];
+ break;
+ default:
+ debug_assert(!"invalid command!\n");
+ }
+}
+
+
+static void stroke_bw_itr_coords(struct stroke_iterator *itr, VGfloat *coords)
+{
+ if (itr->position >= itr->num_commands)
+ return;
+ switch (stroke_itr_command(itr)) {
+ case VG_MOVE_TO_ABS:
+ coords[0] = itr->coords[itr->coord_position];
+ coords[1] = itr->coords[itr->coord_position + 1];
+ break;
+ case VG_LINE_TO_ABS:
+ coords[0] = itr->coords[itr->coord_position];
+ coords[1] = itr->coords[itr->coord_position + 1];
+ break;
+ case VG_CUBIC_TO_ABS:
+ coords[0] = itr->coords[itr->coord_position + 4];
+ coords[1] = itr->coords[itr->coord_position + 5];
+ coords[2] = itr->coords[itr->coord_position + 2];
+ coords[3] = itr->coords[itr->coord_position + 3];
+ coords[4] = itr->coords[itr->coord_position + 0];
+ coords[5] = itr->coords[itr->coord_position + 1];
+ break;
+ default:
+ debug_assert(!"invalid command!\n");
+ }
+}
+
+
+static VGPathCommand stroke_fw_current_command(struct stroke_iterator *it)
+{
+ return it->cmds[it->position];
+}
+
+static VGPathCommand stroke_bw_current_command(struct stroke_iterator *it)
+{
+ VGPathCommand prev_cmd;
+ if (it->position == it->num_commands -1)
+ return VG_MOVE_TO_ABS;
+
+ prev_cmd = it->cmds[it->position + 1];
+ return prev_cmd;
+}
+
+static VGboolean stroke_fw_has_next(struct stroke_iterator *itr)
+{
+ return itr->position < (itr->num_commands - 1);
+}
+
+static VGboolean stroke_bw_has_next(struct stroke_iterator *itr)
+{
+ return itr->position > 0;
+}
+
+static void stroke_fw_next(struct stroke_iterator *itr)
+{
+ VGubyte cmd;
+ debug_assert(stroke_fw_has_next(itr));
+
+ cmd = stroke_itr_command(itr);
+
+ itr->coord_position += num_elements_for_segments(&cmd, 1);
+ ++itr->position;
+}
+
+static void stroke_bw_next(struct stroke_iterator *itr)
+{
+ VGubyte cmd;
+ debug_assert(stroke_bw_has_next(itr));
+
+ --itr->position;
+ cmd = stroke_itr_command(itr);
+
+ itr->coord_position -= num_elements_for_segments(&cmd, 1);
+}
+
+static void stroke_itr_common_init(struct stroke_iterator *itr,
+ struct array *cmds,
+ struct array *coords)
+{
+ itr->cmds = (VGubyte*)cmds->data;
+ itr->num_commands = cmds->num_elements;
+
+ itr->coords = (VGfloat*)coords->data;
+ itr->num_coords = coords->num_elements;
+}
+
+static void stroke_forward_iterator(struct stroke_iterator *itr,
+ struct array *cmds,
+ struct array *coords)
+{
+ stroke_itr_common_init(itr, cmds, coords);
+ itr->position = 0;
+ itr->coord_position = 0;
+
+ itr->next = stroke_fw_next;
+ itr->has_next = stroke_fw_has_next;
+ itr->current_command = stroke_fw_current_command;
+ itr->current_coords = stroke_fw_itr_coords;
+}
+
+static void stroke_backward_iterator(struct stroke_iterator *itr,
+ struct array *cmds,
+ struct array *coords)
+{
+ VGubyte cmd;
+ stroke_itr_common_init(itr, cmds, coords);
+ itr->position = itr->num_commands - 1;
+
+ cmd = stroke_bw_current_command(itr);
+ itr->coord_position = itr->num_coords -
+ num_elements_for_segments(&cmd, 1);
+
+ itr->next = stroke_bw_next;
+ itr->has_next = stroke_bw_has_next;
+ itr->current_command = stroke_bw_current_command;
+ itr->current_coords = stroke_bw_itr_coords;
+}
+
+
+
+static void stroke_flat_next(struct stroke_iterator *itr)
+{
+ VGubyte cmd;
+
+ if (itr->curve_index >= 0) {
+ ++itr->curve_index;
+ if (itr->curve_index >= polygon_vertex_count(itr->curve_poly)) {
+ itr->curve_index = -1;
+ polygon_destroy(itr->curve_poly);
+ itr->curve_poly = 0;
+ } else
+ return;
+ }
+ debug_assert(stroke_fw_has_next(itr));
+
+ cmd = itr->cmds[itr->position];
+ itr->coord_position += num_elements_for_segments(&cmd, 1);
+ ++itr->position;
+
+ cmd = itr->cmds[itr->position];
+
+ if (cmd == VG_CUBIC_TO_ABS) {
+ struct bezier bezier;
+ VGfloat bez[8];
+
+ bez[0] = itr->coords[itr->coord_position - 2];
+ bez[1] = itr->coords[itr->coord_position - 1];
+ bez[2] = itr->coords[itr->coord_position];
+ bez[3] = itr->coords[itr->coord_position + 1];
+ bez[4] = itr->coords[itr->coord_position + 2];
+ bez[5] = itr->coords[itr->coord_position + 3];
+ bez[6] = itr->coords[itr->coord_position + 4];
+ bez[7] = itr->coords[itr->coord_position + 5];
+
+ bezier_init(&bezier,
+ bez[0], bez[1],
+ bez[2], bez[3],
+ bez[4], bez[5],
+ bez[6], bez[7]);
+ /* skip the first one, it's the same as the prev point */
+ itr->curve_index = 1;
+ if (itr->curve_poly) {
+ polygon_destroy(itr->curve_poly);
+ itr->curve_poly = 0;
+ }
+ itr->curve_poly = bezier_to_polygon(&bezier);
+ }
+}
+
+static VGboolean stroke_flat_has_next(struct stroke_iterator *itr)
+{
+ return (itr->curve_index >= 0 &&
+ itr->curve_index < (polygon_vertex_count(itr->curve_poly)-1))
+ || itr->position < (itr->num_commands - 1);
+}
+
+static VGPathCommand stroke_flat_current_command(struct stroke_iterator *it)
+{
+ if (it->cmds[it->position] == VG_CUBIC_TO_ABS) {
+ return VG_LINE_TO_ABS;
+ }
+ return it->cmds[it->position];
+}
+
+static void stroke_flat_itr_coords(struct stroke_iterator *itr, VGfloat *coords)
+{
+ if (itr->curve_index <= -1 && itr->position >= itr->num_commands)
+ return;
+
+ if (itr->curve_index >= 0) {
+ polygon_vertex(itr->curve_poly, itr->curve_index,
+ coords);
+ return;
+ }
+
+ switch (stroke_itr_command(itr)) {
+ case VG_MOVE_TO_ABS:
+ coords[0] = itr->coords[itr->coord_position];
+ coords[1] = itr->coords[itr->coord_position + 1];
+ break;
+ case VG_LINE_TO_ABS:
+ coords[0] = itr->coords[itr->coord_position];
+ coords[1] = itr->coords[itr->coord_position + 1];
+ break;
+ case VG_CUBIC_TO_ABS:
+ default:
+ debug_assert(!"invalid command!\n");
+ }
+}
+
+static void stroke_flat_iterator(struct stroke_iterator *itr,
+ struct array *cmds,
+ struct array *coords)
+{
+ stroke_itr_common_init(itr, cmds, coords);
+ itr->position = 0;
+ itr->coord_position = 0;
+
+ itr->next = stroke_flat_next;
+ itr->has_next = stroke_flat_has_next;
+ itr->current_command = stroke_flat_current_command;
+ itr->current_coords = stroke_flat_itr_coords;
+ itr->curve_index = -1;
+ itr->curve_poly = 0;
+}
+
+
+static INLINE VGboolean finite_coords4(const VGfloat *c)
+{
+ return
+ isfinite(c[0]) && isfinite(c[1]) &&
+ isfinite(c[2]) && isfinite(c[3]);
+}
+
+/* from Graphics Gems II */
+#define SAME_SIGNS(a, b) ((a) * (b) >= 0)
+static VGboolean do_lines_intersect(VGfloat x1, VGfloat y1, VGfloat x2, VGfloat y2,
+ VGfloat x3, VGfloat y3, VGfloat x4, VGfloat y4)
+{
+ VGfloat a1, a2, b1, b2, c1, c2; /* Coefficients of line eqns */
+ VGfloat r1, r2, r3, r4; /* 'sign' values */
+
+ a1 = y2 - y1;
+ b1 = x1 - x2;
+ c1 = x2 * y1 - x1 * y2;
+
+ r3 = a1 * x3 + b1 * y3 + c1;
+ r4 = a1 * x4 + b1 * y4 + c1;
+
+ if (r3 != 0 && r4 != 0 && SAME_SIGNS(r3, r4))
+ return VG_FALSE;
+
+ a2 = y4 - y3;
+ b2 = x3 - x4;
+ c2 = x4 * y3 - x3 * y4;
+
+ r1 = a2 * x1 + b2 * y1 + c2;
+ r2 = a2 * x2 + b2 * y2 + c2;
+
+ if (r1 != 0 && r2 != 0 && SAME_SIGNS(r1, r2))
+ return VG_FALSE;
+
+ return VG_TRUE;
+}
+
+static INLINE VGfloat line_dx(const VGfloat *l)
+{
+ return l[2] - l[0];
+}
+
+static INLINE VGfloat line_dy(const VGfloat *l)
+{
+ return l[3] - l[1];
+}
+
+static INLINE VGfloat line_angle(const VGfloat *l)
+{
+ const VGfloat dx = line_dx(l);
+ const VGfloat dy = line_dy(l);
+
+ const VGfloat theta = atan2(-dy, dx) * 360.0 / M_2PI;
+
+ const VGfloat theta_normalized = theta < 0 ? theta + 360 : theta;
+
+ if (floatsEqual(theta_normalized, 360.f))
+ return 0;
+ else
+ return theta_normalized;
+}
+
+static INLINE void line_set_length(VGfloat *l, VGfloat len)
+{
+ VGfloat uv[] = {l[0], l[1], l[2], l[3]};
+ if (null_line(l))
+ return;
+ line_normalize(uv);
+ l[2] = l[0] + line_dx(uv) * len;
+ l[3] = l[1] + line_dy(uv) * len;
+}
+
+static INLINE void line_translate(VGfloat *l, VGfloat x, VGfloat y)
+{
+ l[0] += x;
+ l[1] += y;
+ l[2] += x;
+ l[3] += y;
+}
+
+static INLINE VGfloat line_angle_to(const VGfloat *l1,
+ const VGfloat *l2)
+{
+ VGfloat a1, a2, delta, delta_normalized;
+ if (null_line(l1) || null_line(l1))
+ return 0;
+
+ a1 = line_angle(l1);
+ a2 = line_angle(l2);
+
+ delta = a2 - a1;
+ delta_normalized = delta < 0 ? delta + 360 : delta;
+
+ if (floatsEqual(delta, 360.f))
+ return 0;
+ else
+ return delta_normalized;
+}
+
+static INLINE VGfloat line_angles(const VGfloat *l1,
+ const VGfloat *l2)
+{
+ VGfloat cos_line, rad = 0;
+
+ if (null_line(l1) || null_line(l2))
+ return 0;
+
+ cos_line = (line_dx(l1)*line_dx(l2) + line_dy(l1)*line_dy(l2)) /
+ (line_lengthv(l1)*line_lengthv(l2));
+ rad = 0;
+
+ if (cos_line >= -1.0 && cos_line <= 1.0)
+ rad = acos(cos_line);
+ return rad * 360 / M_2PI;
+}
+
+
+static INLINE VGfloat adapted_angle_on_x(const VGfloat *line)
+{
+ const VGfloat identity[] = {0, 0, 1, 0};
+ VGfloat angle = line_angles(line, identity);
+ if (line_dy(line) > 0)
+ angle = 360 - angle;
+ return angle;
+}
+
+static enum intersection_type line_intersect(const VGfloat *l1,
+ const VGfloat *l2,
+ float *intersection_point)
+{
+ VGfloat isect[2];
+ enum intersection_type type;
+ VGboolean dx_zero, ldx_zero;
+
+ if (null_line(l1) || null_line(l2) ||
+ !finite_coords4(l1) || !finite_coords4(l2))
+ return NoIntersections;
+
+ type = do_lines_intersect(l1[0], l1[1], l1[2], l1[3], l2[0], l2[1], l2[2], l2[3])
+ ? BoundedIntersection : UnboundedIntersection;
+
+ dx_zero = floatsEqual(line_dx(l1) + 1, 1);
+ ldx_zero = floatsEqual(line_dx(l2) + 1, 1);
+
+ /* one of the lines is vertical */
+ if (dx_zero && ldx_zero) {
+ type = NoIntersections;
+ } else if (dx_zero) {
+ VGfloat la = line_dy(l2) / line_dx(l2);
+ isect[0] = l1[0];
+ isect[1] = la * l1[0] + l2[1] - la * l2[0];
+ } else if (ldx_zero) {
+ VGfloat ta = line_dy(l1) / line_dx(l1);
+ isect[0] = l2[0];
+ isect[1] = ta * l2[0] + l1[1] - ta*l1[0];
+ } else {
+ VGfloat x;
+ VGfloat ta = line_dy(l1) / line_dx(l1);
+ VGfloat la = line_dy(l2) / line_dx(l2);
+ if (ta == la)
+ return NoIntersections;
+
+ x = ( - l2[1] + la * l2[0] + l1[1] - ta * l1[0] ) / (la - ta);
+ isect[0] = x;
+ isect[1] = ta*(x - l1[0]) + l1[1];
+ }
+ if (intersection_point) {
+ intersection_point[0] = isect[0];
+ intersection_point[1] = isect[1];
+ }
+ return type;
+}
+
+static INLINE enum line_join_mode stroker_join_mode(struct stroker *s)
+{
+ switch(s->join_style) {
+ case VG_JOIN_MITER:
+ return MiterJoin;
+ case VG_JOIN_ROUND:
+ return RoundJoin;
+ case VG_JOIN_BEVEL:
+ return FlatJoin;
+ default:
+ return FlatJoin;
+ }
+}
+
+static INLINE enum line_join_mode stroker_cap_mode(struct stroker *s)
+{
+ switch(s->cap_style) {
+ case VG_CAP_BUTT:
+ return FlatJoin;
+ case VG_CAP_ROUND:
+ return RoundCap;
+ case VG_CAP_SQUARE:
+ return SquareJoin;
+ default:
+ return FlatJoin;
+ }
+}
+
+void stroker_emit_move_to(struct stroker *stroker, VGfloat x, VGfloat y)
+{
+ VGubyte cmds = VG_MOVE_TO_ABS;
+ VGfloat coords[2] = {x, y};
+#if DEBUG_EMITS
+ debug_printf("emit move %f, %f\n", x, y);
+#endif
+ stroker->back2_x = stroker->back1_x;
+ stroker->back2_y = stroker->back1_y;
+ stroker->back1_x = x;
+ stroker->back1_y = y;
+
+ path_append_data(stroker->path,
+ 1,
+ &cmds, &coords);
+}
+
+void stroker_emit_line_to(struct stroker *stroker, VGfloat x, VGfloat y)
+{
+ VGubyte cmds = VG_LINE_TO_ABS;
+ VGfloat coords[2] = {x, y};
+#if DEBUG_EMITS
+ debug_printf("emit line %f, %f\n", x, y);
+#endif
+ stroker->back2_x = stroker->back1_x;
+ stroker->back2_y = stroker->back1_y;
+ stroker->back1_x = x;
+ stroker->back1_y = y;
+ path_append_data(stroker->path,
+ 1,
+ &cmds, &coords);
+}
+
+void stroker_emit_curve_to(struct stroker *stroker, VGfloat px1, VGfloat py1,
+ VGfloat px2, VGfloat py2,
+ VGfloat x, VGfloat y)
+{
+ VGubyte cmds = VG_CUBIC_TO_ABS;
+ VGfloat coords[6] = {px1, py1, px2, py2, x, y};
+#if DEBUG_EMITS
+ debug_printf("emit curve %f, %f, %f, %f, %f, %f\n", px1, py1,
+ px2, py2, x, y);
+#endif
+
+ if (px2 == x && py2 == y) {
+ if (px1 == x && py1 == y) {
+ stroker->back2_x = stroker->back1_x;
+ stroker->back2_y = stroker->back1_y;
+ } else {
+ stroker->back2_x = px1;
+ stroker->back2_y = py1;
+ }
+ } else {
+ stroker->back2_x = px2;
+ stroker->back2_y = py2;
+ }
+ stroker->back1_x = x;
+ stroker->back1_y = y;
+
+ path_append_data(stroker->path,
+ 1,
+ &cmds, &coords);
+}
+
+static INLINE void create_round_join(struct stroker *stroker,
+ VGfloat x1, VGfloat y1,
+ VGfloat x2, VGfloat y2,
+ VGfloat width, VGfloat height)
+{
+ struct arc arc;
+ struct matrix matrix;
+
+ matrix_load_identity(&matrix);
+
+ /*stroker_emit_line_to(stroker, nx, ny);*/
+
+ arc_init(&arc, VG_SCCWARC_TO_ABS,
+ x1, y1, x2, y2, width/2, height/2, 0);
+ arc_stroker_emit(&arc, stroker, &matrix);
+}
+
+
+static void create_joins(struct stroker *stroker,
+ VGfloat focal_x, VGfloat focal_y,
+ const VGfloat *next_line, enum line_join_mode join)
+{
+#if DEBUG_EMITS
+ debug_printf("create_joins: focal=[%f, %f], next_line=[%f, %f,%f, %f]\n",
+ focal_x, focal_y,
+ next_line[0], next_line[1], next_line[2], next_line[3]);
+#endif
+ /* if we're alredy connected do nothing */
+ if (floatsEqual(stroker->back1_x, next_line[0]) &&
+ floatsEqual(stroker->back1_y, next_line[1]))
+ return;
+
+ if (join == FlatJoin) {
+ stroker_emit_line_to(stroker, next_line[0], next_line[1]);
+ } else {
+ VGfloat prev_line[] = {stroker->back2_x, stroker->back2_y,
+ stroker->back1_x, stroker->back1_y};
+
+ VGfloat isect[2];
+ enum intersection_type type = line_intersect(prev_line, next_line, isect);
+
+ if (join == SquareJoin) {
+ VGfloat offset = stroker->stroke_width / 2;
+ VGfloat l1[4] = {prev_line[0],
+ prev_line[1],
+ prev_line[2],
+ prev_line[3]};
+ VGfloat l2[4] = {next_line[2],
+ next_line[3],
+ next_line[0],
+ next_line[1]};
+
+ line_translate(l1, line_dx(l1), line_dy(l1));
+ line_set_length(l1, offset);
+
+ line_translate(l2, line_dx(l2), line_dy(l2));
+ line_set_length(l2, offset);
+
+ stroker_emit_line_to(stroker, l1[2], l1[3]);
+ stroker_emit_line_to(stroker, l2[2], l2[3]);
+ stroker_emit_line_to(stroker, l2[0], l2[1]);
+ } else if (join == RoundJoin) {
+ VGfloat offset = stroker->stroke_width / 2;
+ VGfloat short_cut[4] = {prev_line[2], prev_line[3],
+ next_line[0], next_line[1]};
+ VGfloat angle = line_angles(prev_line, short_cut);
+
+ if (type == BoundedIntersection ||
+ (angle > 90 && !floatsEqual(angle, 90.f))) {
+ stroker_emit_line_to(stroker, next_line[0], next_line[1]);
+ return;
+ }
+ create_round_join(stroker, prev_line[2], prev_line[3],
+ next_line[0], next_line[1],
+ offset * 2, offset * 2);
+
+ stroker_emit_line_to(stroker, next_line[0], next_line[1]);
+ } else if (join == RoundCap) {
+ VGfloat offset = stroker->stroke_width / 2;
+ VGfloat l1[4] = { prev_line[0], prev_line[1],
+ prev_line[2], prev_line[3] };
+ VGfloat l2[4] = {focal_x, focal_y,
+ prev_line[2], prev_line[3]};
+
+ line_translate(l1, line_dx(l1), line_dy(l1));
+ line_set_length(l1, KAPPA * offset);
+
+ /* normal between prev_line and focal */
+ line_translate(l2, -line_dy(l2), line_dx(l2));
+ line_set_length(l2, KAPPA * offset);
+
+ stroker_emit_curve_to(stroker, l1[2], l1[3],
+ l2[2], l2[3],
+ l2[0], l2[1]);
+
+ l2[0] = l2[0];
+ l2[1] = l2[1];
+ l2[2] = l2[0] - line_dx(l2);
+ l2[3] = l2[1] - line_dy(l2);
+
+ line_translate(l1, next_line[0] - l1[0], next_line[1] - l1[1]);
+
+ stroker_emit_curve_to(stroker,
+ l2[2], l2[3],
+ l1[2], l1[3],
+ l1[0], l1[1]);
+ } else if (join == MiterJoin) {
+ VGfloat miter_line[4] = {stroker->back1_x, stroker->back1_y,
+ isect[0], isect[1]};
+ VGfloat sl = (stroker->stroke_width * stroker->miter_limit);
+ VGfloat inside_line[4] = {prev_line[2], prev_line[3],
+ next_line[0], next_line[1]};
+ VGfloat angle = line_angle_to(inside_line, prev_line);
+
+ if (type == BoundedIntersection ||
+ (angle > 90 && !floatsEqual(angle, 90.f))) {
+ /*
+ debug_printf("f = %f, nl = %f, pl = %f, is = %f\n",
+ focal_x, next_line[0],
+ prev_line[2], isect[0]);*/
+ stroker_emit_line_to(stroker, next_line[0], next_line[1]);
+ return;
+ }
+
+ if (type == NoIntersections || line_lengthv(miter_line) > sl) {
+ stroker_emit_line_to(stroker, next_line[0], next_line[1]);
+ } else {
+ stroker_emit_line_to(stroker, isect[0], isect[1]);
+ stroker_emit_line_to(stroker, next_line[0], next_line[1]);
+ }
+ } else {
+ debug_assert(!"create_joins bad join style");
+ }
+ }
+}
+
+static void stroker_add_segment(struct stroker *stroker,
+ VGPathCommand cmd,
+ const VGfloat *coords,
+ VGint num_coords)
+{
+ /* skip duplicated points */
+ if (stroker->segments->num_elements &&
+ stroker->last_cmd == cmd) {
+ VGfloat *data = stroker->control_points->data;
+ data += stroker->control_points->num_elements;
+ data -= num_coords;
+ switch (cmd) {
+ case VG_MOVE_TO_ABS:
+ if (floatsEqual(coords[0], data[0]) &&
+ floatsEqual(coords[1], data[1]))
+ return;
+ break;
+ case VG_LINE_TO_ABS:
+ if (floatsEqual(coords[0], data[0]) &&
+ floatsEqual(coords[1], data[1]))
+ return;
+ break;
+ case VG_CUBIC_TO_ABS:
+ if (floatsEqual(coords[0], data[0]) &&
+ floatsEqual(coords[1], data[1]) &&
+ floatsEqual(coords[2], data[2]) &&
+ floatsEqual(coords[3], data[3]) &&
+ floatsEqual(coords[4], data[4]) &&
+ floatsEqual(coords[5], data[5]))
+ return;
+ break;
+ default:
+ debug_assert(!"Invalid stroke segment");
+ }
+ } else if (stroker->last_cmd == VG_CUBIC_TO_ABS &&
+ cmd == VG_LINE_TO_ABS) {
+ VGfloat *data = stroker->control_points->data;
+ data += stroker->control_points->num_elements;
+ data -= 2;
+ if (floatsEqual(coords[0], data[0]) &&
+ floatsEqual(coords[1], data[1]))
+ return;
+ }
+ stroker->last_cmd = cmd;
+ array_append_data(stroker->segments, &cmd, 1);
+ array_append_data(stroker->control_points, coords, num_coords);
+}
+
+void stroker_move_to(struct stroker *stroker, VGfloat x, VGfloat y)
+{
+ VGfloat coords[2] = {x, y};
+#if STROKE_SEGMENTS
+ debug_printf("stroker_move_to(%f, %f)\n", x, y);
+#endif
+
+ if (stroker->segments->num_elements > 0)
+ stroker->process_subpath(stroker);
+
+ array_reset(stroker->segments);
+ array_reset(stroker->control_points);
+
+ stroker_add_segment(stroker, VG_MOVE_TO_ABS, coords, 2);
+}
+
+void stroker_line_to(struct stroker *stroker, VGfloat x, VGfloat y)
+{
+ VGfloat coords[] = {x, y};
+
+#if STROKE_SEGMENTS
+ debug_printf("stroker_line_to(%f, %f)\n", x, y);
+#endif
+ if (!stroker->segments->num_elements)
+ stroker_add_segment(stroker, VG_MOVE_TO_ABS, zero_coords, 2);
+
+ stroker_add_segment(stroker, VG_LINE_TO_ABS, coords, 2);
+}
+
+void stroker_curve_to(struct stroker *stroker, VGfloat px1, VGfloat py1,
+ VGfloat px2, VGfloat py2,
+ VGfloat x, VGfloat y)
+{
+ VGfloat coords[] = {px1, py1,
+ px2, py2,
+ x, y};
+#if STROKE_SEGMENTS
+ debug_printf("stroker_curve_to(%f, %f, %f, %f, %f, %f)\n",
+ px1, py1, px2, py2, x, y);
+#endif
+ if (!stroker->segments->num_elements)
+ stroker_add_segment(stroker, VG_MOVE_TO_ABS, zero_coords, 2);
+
+ stroker_add_segment(stroker, VG_CUBIC_TO_ABS, coords, 6);
+}
+
+static INLINE VGboolean is_segment_null(VGPathCommand cmd,
+ VGfloat *coords,
+ VGfloat *res)
+{
+ switch(cmd) {
+ case VG_MOVE_TO_ABS:
+ case VG_LINE_TO_ABS:
+ return floatsEqual(coords[0], res[0]) &&
+ floatsEqual(coords[1], res[1]);
+ break;
+ case VG_CUBIC_TO_ABS:
+ return floatsEqual(coords[0], res[0]) &&
+ floatsEqual(coords[1], res[1]) &&
+ floatsEqual(coords[2], res[0]) &&
+ floatsEqual(coords[3], res[1]) &&
+ floatsEqual(coords[4], res[0]) &&
+ floatsEqual(coords[5], res[1]);
+ break;
+ default:
+ assert(0);
+ }
+ return VG_FALSE;
+}
+
+static VGboolean vg_stroke_outline(struct stroke_iterator *it,
+ struct stroker *stroker,
+ VGboolean cap_first,
+ VGfloat *start_tangent)
+{
+ const int MAX_OFFSET = 16;
+ struct bezier offset_curves[MAX_OFFSET];
+ VGPathCommand first_element;
+ VGfloat start[2], prev[2];
+ VGboolean first = VG_TRUE;
+ VGfloat offset;
+
+ first_element = stroke_itr_command(it);
+ if (first_element != VG_MOVE_TO_ABS) {
+ stroker_emit_move_to(stroker, 0.f, 0.f);
+ prev[0] = 0.f;
+ prev[1] = 0.f;
+ }
+ stroke_itr_coords(it, start);
+#if STROKE_DEBUG
+ debug_printf(" -> (side) [%.2f, %.2f]\n",
+ start[0],
+ start[1]);
+#endif
+
+ prev[0] = start[0];
+ prev[1] = start[1];
+
+ offset = stroker->stroke_width / 2;
+
+ if (!it->has_next(it)) {
+ /* single point */
+
+ return VG_TRUE;
+ }
+
+ while (it->has_next(it)) {
+ VGPathCommand cmd;
+ VGfloat coords[8];
+
+ it->next(it);
+ cmd = stroke_itr_command(it);
+ stroke_itr_coords(it, coords);
+
+ if (cmd == VG_LINE_TO_ABS) {
+ VGfloat line[4] = {prev[0], prev[1], coords[0], coords[1]};
+ VGfloat normal[4];
+ line_normal(line, normal);
+
+#if STROKE_DEBUG
+ debug_printf("\n ---> (side) lineto [%.2f, %.2f]\n", coords[0], coords[1]);
+#endif
+ line_set_length(normal, offset);
+ line_translate(line, line_dx(normal), line_dy(normal));
+
+ /* if we are starting a new subpath, move to correct starting point */
+ if (first) {
+ if (cap_first)
+ create_joins(stroker, prev[0], prev[1], line,
+ stroker_cap_mode(stroker));
+ else
+ stroker_emit_move_to(stroker, line[0], line[1]);
+ memcpy(start_tangent, line,
+ sizeof(VGfloat) * 4);
+ first = VG_FALSE;
+ } else {
+ create_joins(stroker, prev[0], prev[1], line,
+ stroker_join_mode(stroker));
+ }
+
+ /* add the stroke for this line */
+ stroker_emit_line_to(stroker, line[2], line[3]);
+ prev[0] = coords[0];
+ prev[1] = coords[1];
+ } else if (cmd == VG_CUBIC_TO_ABS) {
+#if STROKE_DEBUG
+ debug_printf("\n ---> (side) cubicTo [%.2f, %.2f]\n",
+ coords[4],
+ coords[5]);
+#endif
+ struct bezier bezier;
+ int count;
+
+ bezier_init(&bezier,
+ prev[0], prev[1], coords[0], coords[1],
+ coords[2], coords[3], coords[4], coords[5]);
+
+ count = bezier_translate_by_normal(&bezier,
+ offset_curves,
+ MAX_OFFSET,
+ offset,
+ curve_threshold);
+
+ if (count) {
+ /* if we are starting a new subpath, move to correct starting point */
+ VGfloat tangent[4];
+ VGint i;
+
+ bezier_start_tangent(&bezier, tangent);
+ line_translate(tangent,
+ offset_curves[0].x1 - bezier.x1,
+ offset_curves[0].y1 - bezier.y1);
+ if (first) {
+ VGfloat pt[2] = {offset_curves[0].x1,
+ offset_curves[0].y1};
+
+ if (cap_first) {
+ create_joins(stroker, prev[0], prev[1], tangent,
+ stroker_cap_mode(stroker));
+ } else {
+ stroker_emit_move_to(stroker, pt[0], pt[1]);
+ }
+ start_tangent[0] = tangent[0];
+ start_tangent[1] = tangent[1];
+ start_tangent[2] = tangent[2];
+ start_tangent[3] = tangent[3];
+ first = VG_FALSE;
+ } else {
+ create_joins(stroker, prev[0], prev[1], tangent,
+ stroker_join_mode(stroker));
+ }
+
+ /* add these beziers */
+ for (i = 0; i < count; ++i) {
+ struct bezier *bez = &offset_curves[i];
+ stroker_emit_curve_to(stroker,
+ bez->x2, bez->y2,
+ bez->x3, bez->y3,
+ bez->x4, bez->y4);
+ }
+ }
+
+ prev[0] = coords[4];
+ prev[1] = coords[5];
+ }
+ }
+
+ if (floatsEqual(start[0], prev[0]) &&
+ floatsEqual(start[1], prev[1])) {
+ /* closed subpath, join first and last point */
+#if STROKE_DEBUG
+ debug_printf("\n stroker: closed subpath\n");
+#endif
+ create_joins(stroker, prev[0], prev[1], start_tangent,
+ stroker_join_mode(stroker));
+ return VG_TRUE;
+ } else {
+#if STROKE_DEBUG
+ debug_printf("\n stroker: open subpath\n");
+#endif
+ return VG_FALSE;
+ }
+}
+
+static void stroker_process_subpath(struct stroker *stroker)
+{
+ VGboolean fwclosed, bwclosed;
+ VGfloat fw_start_tangent[4], bw_start_tangent[4];
+ struct stroke_iterator fwit;
+ struct stroke_iterator bwit;
+ debug_assert(stroker->segments->num_elements > 0);
+
+ memset(fw_start_tangent, 0,
+ sizeof(VGfloat)*4);
+ memset(bw_start_tangent, 0,
+ sizeof(VGfloat)*4);
+
+ stroke_forward_iterator(&fwit, stroker->segments,
+ stroker->control_points);
+ stroke_backward_iterator(&bwit, stroker->segments,
+ stroker->control_points);
+
+ debug_assert(fwit.cmds[0] == VG_MOVE_TO_ABS);
+
+ fwclosed = vg_stroke_outline(&fwit, stroker, VG_FALSE, fw_start_tangent);
+ bwclosed = vg_stroke_outline(&bwit, stroker, !fwclosed, bw_start_tangent);
+
+ if (!bwclosed)
+ create_joins(stroker,
+ fwit.coords[0], fwit.coords[1], fw_start_tangent,
+ stroker_cap_mode(stroker));
+ else {
+ /* hack to handle the requirement of the VG spec that says that strokes
+ * of len==0 that have butt cap or round cap still need
+ * to be rendered. (8.7.4 Stroke Generation) */
+ if (stroker->segments->num_elements <= 3) {
+ VGPathCommand cmd;
+ VGfloat data[8], coords[8];
+ struct stroke_iterator *it = &fwit;
+
+ stroke_forward_iterator(it, stroker->segments,
+ stroker->control_points);
+ cmd = stroke_itr_command(it);
+ stroke_itr_coords(it, coords);
+ if (cmd != VG_MOVE_TO_ABS) {
+ memset(data, 0, sizeof(VGfloat) * 8);
+ if (!is_segment_null(cmd, coords, data))
+ return;
+ } else {
+ data[0] = coords[0];
+ data[1] = coords[1];
+ }
+ while (it->has_next(it)) {
+ it->next(it);
+ cmd = stroke_itr_command(it);
+ stroke_itr_coords(it, coords);
+ if (!is_segment_null(cmd, coords, data))
+ return;
+ }
+ /* generate the square/round cap */
+ if (stroker->cap_style == VG_CAP_SQUARE) {
+ VGfloat offset = stroker->stroke_width / 2;
+ stroker_emit_move_to(stroker, data[0] - offset,
+ data[1] - offset);
+ stroker_emit_line_to(stroker, data[0] + offset,
+ data[1] - offset);
+ stroker_emit_line_to(stroker, data[0] + offset,
+ data[1] + offset);
+ stroker_emit_line_to(stroker, data[0] - offset,
+ data[1] + offset);
+ stroker_emit_line_to(stroker, data[0] - offset,
+ data[1] - offset);
+ } else if (stroker->cap_style == VG_CAP_ROUND) {
+ VGfloat offset = stroker->stroke_width / 2;
+ VGfloat cx = data[0], cy = data[1];
+ { /*circle */
+ struct arc arc;
+ struct matrix matrix;
+ matrix_load_identity(&matrix);
+
+ stroker_emit_move_to(stroker, cx + offset, cy);
+ arc_init(&arc, VG_SCCWARC_TO_ABS,
+ cx + offset, cy,
+ cx - offset, cy,
+ offset, offset, 0);
+ arc_stroker_emit(&arc, stroker, &matrix);
+ arc_init(&arc, VG_SCCWARC_TO_ABS,
+ cx - offset, cy,
+ cx + offset, cy,
+ offset, offset, 0);
+ arc_stroker_emit(&arc, stroker, &matrix);
+ }
+ }
+ }
+ }
+}
+
+static INLINE VGfloat dash_pattern(struct dash_stroker *stroker,
+ VGint idx)
+{
+ if (stroker->dash_pattern[idx] < 0)
+ return 0.f;
+ return stroker->dash_pattern[idx];
+}
+
+static void dash_stroker_process_subpath(struct stroker *str)
+{
+ struct dash_stroker *stroker = (struct dash_stroker *)str;
+ VGfloat sum_length = 0;
+ VGint i;
+ VGint idash = 0;
+ VGfloat pos = 0;
+ VGfloat elen = 0;
+ VGfloat doffset = stroker->dash_phase;
+ VGfloat estart = 0;
+ VGfloat estop = 0;
+ VGfloat cline[4];
+ struct stroke_iterator it;
+ VGfloat prev[2];
+ VGfloat move_to_pos[2];
+ VGfloat line_to_pos[2];
+
+ VGboolean has_move_to = VG_FALSE;
+
+ stroke_flat_iterator(&it, stroker->base.segments,
+ stroker->base.control_points);
+
+ stroke_itr_coords(&it, prev);
+ move_to_pos[0] = prev[0];
+ move_to_pos[1] = prev[1];
+
+ debug_assert(stroker->dash_pattern_num > 0);
+
+ for (i = 0; i < stroker->dash_pattern_num; ++i) {
+ sum_length += dash_pattern(stroker, i);
+ }
+
+ if (floatIsZero(sum_length)) {
+ return;
+ }
+
+ doffset -= floorf(doffset / sum_length) * sum_length;
+
+ while (!floatIsZero(doffset) && doffset >= dash_pattern(stroker, idash)) {
+ doffset -= dash_pattern(stroker, idash);
+ idash = (idash + 1) % stroker->dash_pattern_num;
+ }
+
+ while (it.has_next(&it)) {
+ VGPathCommand cmd;
+ VGfloat coords[8];
+ VGboolean done;
+
+ it.next(&it);
+ cmd = stroke_itr_command(&it);
+ stroke_itr_coords(&it, coords);
+
+ debug_assert(cmd == VG_LINE_TO_ABS);
+ cline[0] = prev[0];
+ cline[1] = prev[1];
+ cline[2] = coords[0];
+ cline[3] = coords[1];
+
+ elen = line_lengthv(cline);
+
+ estop = estart + elen;
+
+ done = pos >= estop;
+ while (!done) {
+ VGfloat p2[2];
+
+ VGint idash_incr = 0;
+ VGboolean has_offset = doffset > 0;
+ VGfloat dpos = pos + dash_pattern(stroker, idash) - doffset - estart;
+
+ debug_assert(dpos >= 0);
+
+ if (dpos > elen) { /* dash extends this line */
+ doffset = dash_pattern(stroker, idash) - (dpos - elen);
+ pos = estop;
+ done = VG_TRUE;
+ p2[0] = cline[2];
+ p2[1] = cline[3];
+ } else { /* Dash is on this line */
+ line_point_at(cline, dpos/elen, p2);
+ pos = dpos + estart;
+ done = pos >= estop;
+ idash_incr = 1;
+ doffset = 0;
+ }
+
+ if (idash % 2 == 0) {
+ line_to_pos[0] = p2[0];
+ line_to_pos[1] = p2[1];
+
+ if (!has_offset || !has_move_to) {
+ stroker_move_to(&stroker->stroker, move_to_pos[0], move_to_pos[1]);
+ has_move_to = VG_TRUE;
+ }
+ stroker_line_to(&stroker->stroker, line_to_pos[0], line_to_pos[1]);
+ } else {
+ move_to_pos[0] = p2[0];
+ move_to_pos[1] = p2[1];
+ }
+
+ idash = (idash + idash_incr) % stroker->dash_pattern_num;
+ }
+
+ estart = estop;
+ prev[0] = coords[0];
+ prev[1] = coords[1];
+ }
+
+ if (it.curve_poly) {
+ polygon_destroy(it.curve_poly);
+ it.curve_poly = 0;
+ }
+
+ stroker->base.path = stroker->stroker.path;
+}
+
+static void default_begin(struct stroker *stroker)
+{
+ array_reset(stroker->segments);
+ array_reset(stroker->control_points);
+}
+
+static void default_end(struct stroker *stroker)
+{
+ if (stroker->segments->num_elements > 0)
+ stroker->process_subpath(stroker);
+}
+
+
+static void dash_stroker_begin(struct stroker *stroker)
+{
+ struct dash_stroker *dasher =
+ (struct dash_stroker *)stroker;
+
+ default_begin(&dasher->stroker);
+ default_begin(stroker);
+}
+
+static void dash_stroker_end(struct stroker *stroker)
+{
+ struct dash_stroker *dasher =
+ (struct dash_stroker *)stroker;
+
+ default_end(stroker);
+ default_end(&dasher->stroker);
+}
+
+void stroker_init(struct stroker *stroker,
+ struct vg_state *state)
+{
+ stroker->stroke_width = state->stroke.line_width.f;
+ stroker->miter_limit = state->stroke.miter_limit.f;
+ stroker->cap_style = state->stroke.cap_style;
+ stroker->join_style = state->stroke.join_style;
+
+ stroker->begin = default_begin;
+ stroker->process_subpath = stroker_process_subpath;
+ stroker->end = default_end;
+
+ stroker->segments = array_create(sizeof(VGubyte));
+ stroker->control_points = array_create(sizeof(VGfloat));
+
+ stroker->back1_x = 0;
+ stroker->back1_y = 0;
+ stroker->back2_x = 0;
+ stroker->back2_y = 0;
+
+ stroker->path = path_create(VG_PATH_DATATYPE_F, 1.0f, 0.0f,
+ 0, 0, VG_PATH_CAPABILITY_ALL);
+
+ stroker->last_cmd = VG_CLOSE_PATH;
+}
+
+void dash_stroker_init(struct stroker *str,
+ struct vg_state *state)
+{
+ struct dash_stroker *stroker = (struct dash_stroker *)str;
+ int i;
+
+ stroker_init(str, state);
+ stroker_init(&stroker->stroker, state);
+
+ {
+ int real_num = state->stroke.dash_pattern_num;
+ if (real_num % 2)/* if odd, ignore the last one */
+ --real_num;
+ for (i = 0; i < real_num; ++i)
+ stroker->dash_pattern[i] = state->stroke.dash_pattern[i].f;
+ stroker->dash_pattern_num = real_num;
+ }
+
+ stroker->dash_phase = state->stroke.dash_phase.f;
+ stroker->dash_phase_reset = state->stroke.dash_phase_reset;
+
+ stroker->base.begin = dash_stroker_begin;
+ stroker->base.process_subpath = dash_stroker_process_subpath;
+ stroker->base.end = dash_stroker_end;
+ path_destroy(stroker->base.path);
+ stroker->base.path = NULL;
+}
+
+void stroker_begin(struct stroker *stroker)
+{
+ stroker->begin(stroker);
+}
+
+void stroker_end(struct stroker *stroker)
+{
+ stroker->end(stroker);
+}
+
+void stroker_cleanup(struct stroker *stroker)
+{
+ array_destroy(stroker->segments);
+ array_destroy(stroker->control_points);
+}
+
+void dash_stroker_cleanup(struct dash_stroker *stroker)
+{
+ /* if stroker->base.path is null means we never
+ * processed a valid path so delete the temp one
+ * we already created */
+ if (!stroker->base.path)
+ path_destroy(stroker->stroker.path);
+ stroker_cleanup(&stroker->stroker);
+ stroker_cleanup((struct stroker*)stroker);
+}