From 544dd4b11f7be76bb00fe29a60eaf2772dcc69ca Mon Sep 17 00:00:00 2001 From: Zack Rusin Date: Fri, 1 May 2009 12:41:38 -0400 Subject: OpenVG 1.0 State Tracker Import of the OpenVG 1.0 state tracker for Gallium. --- src/gallium/state_trackers/vega/bezier.c | 704 +++++++++++++++++++++++++++++++ 1 file changed, 704 insertions(+) create mode 100644 src/gallium/state_trackers/vega/bezier.c (limited to 'src/gallium/state_trackers/vega/bezier.c') diff --git a/src/gallium/state_trackers/vega/bezier.c b/src/gallium/state_trackers/vega/bezier.c new file mode 100644 index 0000000000..39a7ade016 --- /dev/null +++ b/src/gallium/state_trackers/vega/bezier.c @@ -0,0 +1,704 @@ +/************************************************************************** + * + * 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 "bezier.h" + +#include "matrix.h" +#include "polygon.h" + +#include "pipe/p_compiler.h" +#include "util/u_debug.h" + +#include +#include +#include +#include + +static const float flatness = 0.5; + + +static INLINE void split_left(struct bezier *bez, VGfloat t, struct bezier* left) +{ + left->x1 = bez->x1; + left->y1 = bez->y1; + + left->x2 = bez->x1 + t * (bez->x2 - bez->x1); + left->y2 = bez->y1 + t * (bez->y2 - bez->y1); + + left->x3 = bez->x2 + t * (bez->x3 - bez->x2); + left->y3 = bez->y2 + t * (bez->y3 - bez->y2); + + bez->x3 = bez->x3 + t * (bez->x4 - bez->x3); + bez->y3 = bez->y3 + t * (bez->y4 - bez->y3); + + bez->x2 = left->x3 + t * (bez->x3 - left->x3); + bez->y2 = left->y3 + t * (bez->y3 - left->y3); + + left->x3 = left->x2 + t * (left->x3 - left->x2); + left->y3 = left->y2 + t * (left->y3 - left->y2); + + left->x4 = bez->x1 = left->x3 + t * (bez->x2 - left->x3); + left->y4 = bez->y1 = left->y3 + t * (bez->y2 - left->y3); +} + +static INLINE void split(struct bezier *bez, + struct bezier *first_half, + struct bezier *second_half) +{ + double c = (bez->x2 + bez->x3) * 0.5; + first_half->x2 = (bez->x1 + bez->x2) * 0.5; + second_half->x3 = (bez->x3 + bez->x4) * 0.5; + first_half->x1 = bez->x1; + second_half->x4 = bez->x4; + first_half->x3 = (first_half->x2 + c) * 0.5; + second_half->x2 = (second_half->x3 + c) * 0.5; + first_half->x4 = second_half->x1 = + (first_half->x3 + second_half->x2) * 0.5; + + c = (bez->y2 + bez->y3) / 2; + first_half->y2 = (bez->y1 + bez->y2) * 0.5; + second_half->y3 = (bez->y3 + bez->y4) * 0.5; + first_half->y1 = bez->y1; + second_half->y4 = bez->y4; + first_half->y3 = (first_half->y2 + c) * 0.5; + second_half->y2 = (second_half->y3 + c) * 0.5; + first_half->y4 = second_half->y1 = + (first_half->y3 + second_half->y2) * 0.5; +} + +struct polygon * bezier_to_polygon(struct bezier *bez) +{ + struct polygon *poly = polygon_create(64); + polygon_vertex_append(poly, bez->x1, bez->y1); + bezier_add_to_polygon(bez, poly); + return poly; +} + +void bezier_add_to_polygon(const struct bezier *bez, + struct polygon *poly) +{ + struct bezier beziers[32]; + struct bezier *b; + + beziers[0] = *bez; + b = beziers; + + while (b >= beziers) { + double y4y1 = b->y4 - b->y1; + double x4x1 = b->x4 - b->x1; + double l = ABS(x4x1) + ABS(y4y1); + double d; + if (l > 1.f) { + d = ABS((x4x1)*(b->y1 - b->y2) - (y4y1)*(b->x1 - b->x2)) + + ABS((x4x1)*(b->y1 - b->y3) - (y4y1)*(b->x1 - b->x3)); + } else { + d = ABS(b->x1 - b->x2) + ABS(b->y1 - b->y2) + + ABS(b->x1 - b->x3) + ABS(b->y1 - b->y3); + l = 1.; + } + if (d < flatness*l || b == beziers + 31) { + /* good enough, we pop it off and add the endpoint */ + polygon_vertex_append(poly, b->x4, b->y4); + --b; + } else { + /* split, second half of the bezier goes lower into the stack */ + split(b, b+1, b); + ++b; + } + } +} + +static void add_if_close(struct bezier *bez, VGfloat *length, VGfloat error) +{ + struct bezier left, right; /* bez poly splits */ + VGfloat len = 0.0; /* arc length */ + VGfloat chord; /* chord length */ + + len = len + line_length(bez->x1, bez->y1, bez->x2, bez->y2); + len = len + line_length(bez->x2, bez->y2, bez->x3, bez->y3); + len = len + line_length(bez->x3, bez->y3, bez->x4, bez->y4); + + chord = line_length(bez->x1, bez->y1, bez->x4, bez->y4); + + if ((len-chord) > error) { + split(bez, &left, &right); /* split in two */ + add_if_close(&left, length, error); /* try left side */ + add_if_close(&right, length, error); /* try right side */ + return; + } + + *length = *length + len; + + return; +} + +float bezier_length(struct bezier *bez, float error) +{ + VGfloat length = 0.f; + + add_if_close(bez, &length, error); + return length; +} + +void bezier_init(struct bezier *bez, + float x1, float y1, + float x2, float y2, + float x3, float y3, + float x4, float y4) +{ + bez->x1 = x1; + bez->y1 = y1; + bez->x2 = x2; + bez->y2 = y2; + bez->x3 = x3; + bez->y3 = y3; + bez->x4 = x4; + bez->y4 = y4; +#if 0 + debug_printf("bezier in [%f, %f, %f, %f, %f, %f]\n", + x1, y1, x2, y2, x3, y3, x4, y4); +#endif +} + + +static INLINE void bezier_init2v(struct bezier *bez, + float *pt1, + float *pt2, + float *pt3, + float *pt4) +{ + bez->x1 = pt1[0]; + bez->y1 = pt1[1]; + + bez->x2 = pt2[0]; + bez->y2 = pt2[1]; + + bez->x3 = pt3[0]; + bez->y3 = pt3[1]; + + bez->x4 = pt4[0]; + bez->y4 = pt4[1]; +} + + +void bezier_transform(struct bezier *bez, + struct matrix *matrix) +{ + assert(matrix_is_affine(matrix)); + matrix_map_point(matrix, bez->x1, bez->y1, &bez->x1, &bez->y1); + matrix_map_point(matrix, bez->x2, bez->y2, &bez->x2, &bez->y2); + matrix_map_point(matrix, bez->x3, bez->y3, &bez->x3, &bez->y3); + matrix_map_point(matrix, bez->x4, bez->y4, &bez->x4, &bez->y4); +} + +static INLINE void bezier_point_at(const struct bezier *bez, float t, float *pt) +{ + float a, b, c, d; + float m_t; + m_t = 1. - t; + b = m_t * m_t; + c = t * t; + d = c * t; + a = b * m_t; + b *= 3. * t; + c *= 3. * m_t; + pt[0] = a*bez->x1 + b*bez->x2 + c*bez->x3 + d*bez->x4; + pt[1] = a*bez->y1 + b*bez->y2 + c*bez->y3 + d*bez->y4; +} + +static INLINE void bezier_normal_at(const struct bezier *bez, float t, float *norm) +{ + float m_t = 1. - t; + float a = m_t * m_t; + float b = t * m_t; + float c = t * t; + + norm[0] = (bez->y2-bez->y1) * a + (bez->y3-bez->y2) * b + (bez->y4-bez->y3) * c; + norm[1] = -(bez->x2-bez->x1) * a - (bez->x3-bez->x2) * b - (bez->x4-bez->x3) * c; +} + +enum shift_result { + Ok, + Discard, + Split, + Circle +}; + +static enum shift_result good_offset(const struct bezier *b1, + const struct bezier *b2, + float offset, float threshold) +{ + const float o2 = offset*offset; + const float max_dist_line = threshold*offset*offset; + const float max_dist_normal = threshold*offset; + const float spacing = 0.25; + for (float i = spacing; i < 0.99; i += spacing) { + float p1[2],p2[2], d, l; + float normal[2]; + bezier_point_at(b1, i, p1); + bezier_point_at(b2, i, p2); + d = (p1[0] - p2[0])*(p1[0] - p2[0]) + (p1[1] - p2[1])*(p1[1] - p2[1]); + if (ABS(d - o2) > max_dist_line) + return Split; + + bezier_normal_at(b1, i, normal); + l = ABS(normal[0]) + ABS(normal[1]); + if (l != 0.) { + d = ABS(normal[0]*(p1[1] - p2[1]) - normal[1]*(p1[0] - p2[0]) ) / l; + if (d > max_dist_normal) + return Split; + } + } + return Ok; +} + +static INLINE void shift_line_by_normal(float *l, float offset) +{ + float norm[4]; + float tx, ty; + + line_normal(l, norm); + line_normalize(norm); + + tx = (norm[2] - norm[0]) * offset; + ty = (norm[3] - norm[1]) * offset; + l[0] += tx; l[1] += ty; + l[2] += tx; l[3] += ty; +} + +static INLINE VGboolean is_bezier_line(float (*points)[2], int count) +{ + float dx13 = points[2][0] - points[0][0]; + float dy13 = points[2][1] - points[0][1]; + + float dx12 = points[1][0] - points[0][0]; + float dy12 = points[1][1] - points[0][1]; + + debug_assert(count > 2); + + if (count == 3) { + return floatsEqual(dx12 * dy13, dx13 * dy12); + } else if (count == 4) { + float dx14 = points[3][0] - points[0][0]; + float dy14 = points[3][1] - points[0][1]; + + return (floatsEqual(dx12 * dy13, dx13 * dy12) && + floatsEqual(dx12 * dy14, dx14 * dy12)); + } + + return VG_FALSE; +} + +static INLINE void compute_pt_normal(float *pt1, float *pt2, float *res) +{ + float line[4]; + float normal[4]; + line[0] = 0.f; line[1] = 0.f; + line[2] = pt2[0] - pt1[0]; + line[3] = pt2[1] - pt1[1]; + line_normal(line, normal); + line_normalize(normal); + + res[0] = normal[2]; + res[1] = normal[3]; +} + +static enum shift_result shift(const struct bezier *orig, + struct bezier *shifted, + float offset, float threshold) +{ + int map[4]; + VGboolean p1_p2_equal = (orig->x1 == orig->x2 && orig->y1 == orig->y2); + VGboolean p2_p3_equal = (orig->x2 == orig->x3 && orig->y2 == orig->y3); + VGboolean p3_p4_equal = (orig->x3 == orig->x4 && orig->y3 == orig->y4); + + float points[4][2]; + int np = 0; + float bounds[4]; + float points_shifted[4][2]; + float prev_normal[2]; + + points[np][0] = orig->x1; + points[np][1] = orig->y1; + map[0] = 0; + ++np; + if (!p1_p2_equal) { + points[np][0] = orig->x2; + points[np][1] = orig->y2; + ++np; + } + map[1] = np - 1; + if (!p2_p3_equal) { + points[np][0] = orig->x3; + points[np][1] = orig->y3; + ++np; + } + map[2] = np - 1; + if (!p3_p4_equal) { + points[np][0] = orig->x4; + points[np][1] = orig->y4; + ++np; + } + map[3] = np - 1; + if (np == 1) + return Discard; + + /* We need to specialcase lines of 3 or 4 points due to numerical + instability in intersection code below */ + if (np > 2 && is_bezier_line(points, np)) { + float l[4] = { points[0][0], points[0][1], + points[np-1][0], points[np-1][1] }; + float ctrl1[2], ctrl2[2]; + if (floatsEqual(points[0][0], points[np-1][0]) && + floatsEqual(points[0][1], points[np-1][1])) + return Discard; + + shift_line_by_normal(l, offset); + line_point_at(l, 0.33, ctrl1); + line_point_at(l, 0.66, ctrl2); + bezier_init(shifted, l[0], l[1], + ctrl1[0], ctrl1[1], ctrl2[0], ctrl2[1], + l[2], l[3]); + return Ok; + } + + bezier_bounds(orig, bounds); + if (np == 4 && bounds[2] < .1*offset && bounds[3] < .1*offset) { + float l = (orig->x1 - orig->x2)*(orig->x1 - orig->x2) + + (orig->y1 - orig->y2)*(orig->y1 - orig->y1) * + (orig->x3 - orig->x4)*(orig->x3 - orig->x4) + + (orig->y3 - orig->y4)*(orig->y3 - orig->y4); + float dot = (orig->x1 - orig->x2)*(orig->x3 - orig->x4) + + (orig->y1 - orig->y2)*(orig->y3 - orig->y4); + if (dot < 0 && dot*dot < 0.8*l) + /* the points are close and reverse dirction. Approximate the whole + thing by a semi circle */ + return Circle; + } + + compute_pt_normal(points[0], points[1], prev_normal); + + points_shifted[0][0] = points[0][0] + offset * prev_normal[0]; + points_shifted[0][1] = points[0][1] + offset * prev_normal[1]; + + for (int i = 1; i < np - 1; ++i) { + float normal_sum[2], r; + float next_normal[2]; + compute_pt_normal(points[i], points[i + 1], next_normal); + + normal_sum[0] = prev_normal[0] + next_normal[0]; + normal_sum[1] = prev_normal[1] + next_normal[1]; + + r = 1.0 + prev_normal[0] * next_normal[0] + + prev_normal[1] * next_normal[1]; + + if (floatsEqual(r + 1, 1)) { + points_shifted[i][0] = points[i][0] + offset * prev_normal[0]; + points_shifted[i][1] = points[i][1] + offset * prev_normal[1]; + } else { + float k = offset / r; + points_shifted[i][0] = points[i][0] + k * normal_sum[0]; + points_shifted[i][1] = points[i][1] + k * normal_sum[1]; + } + + prev_normal[0] = next_normal[0]; + prev_normal[1] = next_normal[1]; + } + + points_shifted[np - 1][0] = points[np - 1][0] + offset * prev_normal[0]; + points_shifted[np - 1][1] = points[np - 1][1] + offset * prev_normal[1]; + + bezier_init2v(shifted, + points_shifted[map[0]], points_shifted[map[1]], + points_shifted[map[2]], points_shifted[map[3]]); + + return good_offset(orig, shifted, offset, threshold); +} + +static VGboolean make_circle(const struct bezier *b, float offset, struct bezier *o) +{ + float normals[3][2]; + float dist; + float angles[2]; + float sign = 1.f; + int i; + float circle[3][2]; + + normals[0][0] = b->y2 - b->y1; + normals[0][1] = b->x1 - b->x2; + dist = sqrt(normals[0][0]*normals[0][0] + normals[0][1]*normals[0][1]); + if (floatsEqual(dist + 1, 1.f)) + return VG_FALSE; + normals[0][0] /= dist; + normals[0][1] /= dist; + + normals[2][0] = b->y4 - b->y3; + normals[2][1] = b->x3 - b->x4; + dist = sqrt(normals[2][0]*normals[2][0] + normals[2][1]*normals[2][1]); + if (floatsEqual(dist + 1, 1.f)) + return VG_FALSE; + normals[2][0] /= dist; + normals[2][1] /= dist; + + normals[1][0] = b->x1 - b->x2 - b->x3 + b->x4; + normals[1][1] = b->y1 - b->y2 - b->y3 + b->y4; + dist = -1*sqrt(normals[1][0]*normals[1][0] + normals[1][1]*normals[1][1]); + normals[1][0] /= dist; + normals[1][1] /= dist; + + for (i = 0; i < 2; ++i) { + float cos_a = normals[i][0]*normals[i+1][0] + normals[i][1]*normals[i+1][1]; + if (cos_a > 1.) + cos_a = 1.; + if (cos_a < -1.) + cos_a = -1; + angles[i] = acos(cos_a)/M_PI; + } + + if (angles[0] + angles[1] > 1.) { + /* more than 180 degrees */ + normals[1][0] = -normals[1][0]; + normals[1][1] = -normals[1][1]; + angles[0] = 1. - angles[0]; + angles[1] = 1. - angles[1]; + sign = -1.; + } + + circle[0][0] = b->x1 + normals[0][0]*offset; + circle[0][1] = b->y1 + normals[0][1]*offset; + + circle[1][0] = 0.5*(b->x1 + b->x4) + normals[1][0]*offset; + circle[1][1] = 0.5*(b->y1 + b->y4) + normals[1][1]*offset; + + circle[2][0] = b->x4 + normals[2][0]*offset; + circle[2][1] = b->y4 + normals[2][1]*offset; + + for (i = 0; i < 2; ++i) { + float kappa = 2.*KAPPA * sign * offset * angles[i]; + + o->x1 = circle[i][0]; + o->y1 = circle[i][1]; + o->x2 = circle[i][0] - normals[i][1]*kappa; + o->y2 = circle[i][1] + normals[i][0]*kappa; + o->x3 = circle[i+1][0] + normals[i+1][1]*kappa; + o->y3 = circle[i+1][1] - normals[i+1][0]*kappa; + o->x4 = circle[i+1][0]; + o->y4 = circle[i+1][1]; + + ++o; + } + return VG_TRUE; +} + +int bezier_translate_by_normal(struct bezier *bez, + struct bezier *curves, + int max_curves, + float normal_len, + float threshold) +{ + struct bezier beziers[10]; + struct bezier *b, *o; + + /* fixme: this should really be floatsEqual */ + if (bez->x1 == bez->x2 && bez->x1 == bez->x3 && bez->x1 == bez->x4 && + bez->y1 == bez->y2 && bez->y1 == bez->y3 && bez->y1 == bez->y4) + return 0; + + --max_curves; +redo: + beziers[0] = *bez; + b = beziers; + o = curves; + + while (b >= beziers) { + int stack_segments = b - beziers + 1; + enum shift_result res; + if ((stack_segments == 10) || (o - curves == max_curves - stack_segments)) { + threshold *= 1.5; + if (threshold > 2.) + goto give_up; + goto redo; + } + res = shift(b, o, normal_len, threshold); + if (res == Discard) { + --b; + } else if (res == Ok) { + ++o; + --b; + continue; + } else if (res == Circle && max_curves - (o - curves) >= 2) { + /* add semi circle */ + if (make_circle(b, normal_len, o)) + o += 2; + --b; + } else { + split(b, b+1, b); + ++b; + } + } + +give_up: + while (b >= beziers) { + enum shift_result res = shift(b, o, normal_len, threshold); + + /* if res isn't Ok or Split then *o is undefined */ + if (res == Ok || res == Split) + ++o; + + --b; + } + + debug_assert(o - curves <= max_curves); + return o - curves; +} + +void bezier_bounds(const struct bezier *bez, + float *bounds/*x/y/width/height*/) +{ + float xmin = bez->x1; + float xmax = bez->x1; + float ymin = bez->y1; + float ymax = bez->y1; + + if (bez->x2 < xmin) + xmin = bez->x2; + else if (bez->x2 > xmax) + xmax = bez->x2; + if (bez->x3 < xmin) + xmin = bez->x3; + else if (bez->x3 > xmax) + xmax = bez->x3; + if (bez->x4 < xmin) + xmin = bez->x4; + else if (bez->x4 > xmax) + xmax = bez->x4; + + if (bez->y2 < ymin) + ymin = bez->y2; + else if (bez->y2 > ymax) + ymax = bez->y2; + if (bez->y3 < ymin) + ymin = bez->y3; + else if (bez->y3 > ymax) + ymax = bez->y3; + if (bez->y4 < ymin) + ymin = bez->y4; + else if (bez->y4 > ymax) + ymax = bez->y4; + + bounds[0] = xmin; /* x */ + bounds[1] = ymin; /* y */ + bounds[2] = xmax - xmin; /* width */ + bounds[3] = ymax - ymin; /* height */ +} + +void bezier_start_tangent(const struct bezier *bez, + float *tangent) +{ + tangent[0] = bez->x1; + tangent[1] = bez->y1; + tangent[2] = bez->x2; + tangent[3] = bez->y2; + + if (null_line(tangent)) { + tangent[0] = bez->x1; + tangent[1] = bez->y1; + tangent[2] = bez->x3; + tangent[3] = bez->y3; + } + if (null_line(tangent)) { + tangent[0] = bez->x1; + tangent[1] = bez->y1; + tangent[2] = bez->x4; + tangent[3] = bez->y4; + } +} + + +static INLINE VGfloat bezier_t_at_length(struct bezier *bez, + VGfloat at_length, + VGfloat error) +{ + VGfloat len = bezier_length(bez, error); + VGfloat t = 1.0; + VGfloat last_bigger = 1.; + + if (at_length > len || floatsEqual(at_length, len)) + return t; + + if (floatIsZero(at_length)) + return 0.f; + + t *= 0.5; + while (1) { + struct bezier right = *bez; + struct bezier left; + VGfloat tmp_len; + split_left(&right, t, &left); + tmp_len = bezier_length(&left, error); + if (ABS(tmp_len - at_length) < error) + break; + + if (tmp_len < at_length) { + t += (last_bigger - t)*.5; + } else { + last_bigger = t; + t -= t*.5; + } + } + return t; +} + +void bezier_point_at_length(struct bezier *bez, + float length, + float *point, + float *normal) +{ + /* ~0.000001 seems to be required to pass G2080x tests */ + VGfloat t = bezier_t_at_length(bez, length, 0.000001); + bezier_point_at(bez, t, point); + bezier_normal_at(bez, t, normal); + vector_unit(normal); +} + +void bezier_point_at_t(struct bezier *bez, float t, + float *point, float *normal) +{ + bezier_point_at(bez, t, point); + bezier_normal_at(bez, t, normal); + vector_unit(normal); +} + +void bezier_exact_bounds(const struct bezier *bez, + float *bounds/*x/y/width/height*/) +{ + struct polygon *poly = polygon_create(64); + polygon_vertex_append(poly, bez->x1, bez->y1); + bezier_add_to_polygon(bez, poly); + polygon_bounding_rect(poly, bounds); + polygon_destroy(poly); +} + -- cgit v1.2.3