pixman_fbCombineMaskU
};
-typedef struct
-{
- uint32_t left_ag;
- uint32_t left_rb;
- uint32_t right_ag;
- uint32_t right_rb;
- int32_t left_x;
- int32_t right_x;
- int32_t stepper;
-
- pixman_gradient_stop_t *stops;
- int num_stops;
- unsigned int spread;
-
- int need_reset;
-} GradientWalker;
-
-static void
-_gradient_walker_init (GradientWalker *walker,
- gradient_t *gradient,
- unsigned int spread)
-{
- walker->num_stops = gradient->n_stops;
- walker->stops = gradient->stops;
- walker->left_x = 0;
- walker->right_x = 0x10000;
- walker->stepper = 0;
- walker->left_ag = 0;
- walker->left_rb = 0;
- walker->right_ag = 0;
- walker->right_rb = 0;
- walker->spread = spread;
-
- walker->need_reset = TRUE;
-}
-
-static void
-_gradient_walker_reset (GradientWalker *walker,
- pixman_fixed_32_32_t pos)
-{
- int32_t x, left_x, right_x;
- pixman_color_t *left_c, *right_c;
- int n, count = walker->num_stops;
- pixman_gradient_stop_t * stops = walker->stops;
-
- static const pixman_color_t transparent_black = { 0, 0, 0, 0 };
-
- switch (walker->spread)
- {
- case PIXMAN_REPEAT_NORMAL:
- x = (int32_t)pos & 0xFFFF;
- for (n = 0; n < count; n++)
- if (x < stops[n].x)
- break;
- if (n == 0) {
- left_x = stops[count-1].x - 0x10000;
- left_c = &stops[count-1].color;
- } else {
- left_x = stops[n-1].x;
- left_c = &stops[n-1].color;
- }
-
- if (n == count) {
- right_x = stops[0].x + 0x10000;
- right_c = &stops[0].color;
- } else {
- right_x = stops[n].x;
- right_c = &stops[n].color;
- }
- left_x += (pos - x);
- right_x += (pos - x);
- break;
-
- case PIXMAN_REPEAT_PAD:
- for (n = 0; n < count; n++)
- if (pos < stops[n].x)
- break;
-
- if (n == 0) {
- left_x = INT32_MIN;
- left_c = &stops[0].color;
- } else {
- left_x = stops[n-1].x;
- left_c = &stops[n-1].color;
- }
-
- if (n == count) {
- right_x = INT32_MAX;
- right_c = &stops[n-1].color;
- } else {
- right_x = stops[n].x;
- right_c = &stops[n].color;
- }
- break;
-
- case PIXMAN_REPEAT_REFLECT:
- x = (int32_t)pos & 0xFFFF;
- if ((int32_t)pos & 0x10000)
- x = 0x10000 - x;
- for (n = 0; n < count; n++)
- if (x < stops[n].x)
- break;
-
- if (n == 0) {
- left_x = -stops[0].x;
- left_c = &stops[0].color;
- } else {
- left_x = stops[n-1].x;
- left_c = &stops[n-1].color;
- }
-
- if (n == count) {
- right_x = 0x20000 - stops[n-1].x;
- right_c = &stops[n-1].color;
- } else {
- right_x = stops[n].x;
- right_c = &stops[n].color;
- }
-
- if ((int32_t)pos & 0x10000) {
- pixman_color_t *tmp_c;
- int32_t tmp_x;
-
- tmp_x = 0x10000 - right_x;
- right_x = 0x10000 - left_x;
- left_x = tmp_x;
-
- tmp_c = right_c;
- right_c = left_c;
- left_c = tmp_c;
-
- x = 0x10000 - x;
- }
- left_x += (pos - x);
- right_x += (pos - x);
- break;
-
- default: /* RepeatNone */
- for (n = 0; n < count; n++)
- if (pos < stops[n].x)
- break;
-
- if (n == 0)
- {
- left_x = INT32_MIN;
- right_x = stops[0].x;
- left_c = right_c = (pixman_color_t*) &transparent_black;
- }
- else if (n == count)
- {
- left_x = stops[n-1].x;
- right_x = INT32_MAX;
- left_c = right_c = (pixman_color_t*) &transparent_black;
- }
- else
- {
- left_x = stops[n-1].x;
- right_x = stops[n].x;
- left_c = &stops[n-1].color;
- right_c = &stops[n].color;
- }
- }
-
- walker->left_x = left_x;
- walker->right_x = right_x;
- walker->left_ag = ((left_c->alpha >> 8) << 16) | (left_c->green >> 8);
- walker->left_rb = ((left_c->red & 0xff00) << 8) | (left_c->blue >> 8);
- walker->right_ag = ((right_c->alpha >> 8) << 16) | (right_c->green >> 8);
- walker->right_rb = ((right_c->red & 0xff00) << 8) | (right_c->blue >> 8);
-
- if ( walker->left_x == walker->right_x ||
- ( walker->left_ag == walker->right_ag &&
- walker->left_rb == walker->right_rb ) )
- {
- walker->stepper = 0;
- }
- else
- {
- int32_t width = right_x - left_x;
- walker->stepper = ((1 << 24) + width/2)/width;
- }
-
- walker->need_reset = FALSE;
-}
-
-#define GRADIENT_WALKER_NEED_RESET(w,x) \
- ( (w)->need_reset || (x) < (w)->left_x || (x) >= (w)->right_x)
-
-
-/* the following assumes that GRADIENT_WALKER_NEED_RESET(w,x) is FALSE */
-static uint32_t
-_gradient_walker_pixel (GradientWalker *walker,
- pixman_fixed_32_32_t x)
-{
- int dist, idist;
- uint32_t t1, t2, a, color;
-
- if (GRADIENT_WALKER_NEED_RESET (walker, x))
- _gradient_walker_reset (walker, x);
-
- dist = ((int)(x - walker->left_x)*walker->stepper) >> 16;
- idist = 256 - dist;
-
- /* combined INTERPOLATE and premultiply */
- t1 = walker->left_rb*idist + walker->right_rb*dist;
- t1 = (t1 >> 8) & 0xff00ff;
-
- t2 = walker->left_ag*idist + walker->right_ag*dist;
- t2 &= 0xff00ff00;
-
- color = t2 & 0xff000000;
- a = t2 >> 24;
-
- t1 = t1*a + 0x800080;
- t1 = (t1 + ((t1 >> 8) & 0xff00ff)) >> 8;
-
- t2 = (t2 >> 8)*a + 0x800080;
- t2 = (t2 + ((t2 >> 8) & 0xff00ff));
-
- return (color | (t1 & 0xff00ff) | (t2 & 0xff00));
-}
-
-static void pixmanFetchSourcePict(source_image_t * pict, int x, int y, int width, uint32_t *buffer, uint32_t *mask, uint32_t maskBits)
-{
-#if 0
- SourcePictPtr pGradient = pict->pSourcePict;
-#endif
- GradientWalker walker;
- uint32_t *end = buffer + width;
- gradient_t *gradient;
-
- if (pict->common.type == SOLID)
- {
- register uint32_t color = ((solid_fill_t *)pict)->color;
-
- while (buffer < end)
- *(buffer++) = color;
-
- return;
- }
-
- gradient = (gradient_t *)pict;
-
- _gradient_walker_init (&walker, gradient, pict->common.repeat);
-
- if (pict->common.type == LINEAR) {
- pixman_vector_t v, unit;
- pixman_fixed_32_32_t l;
- pixman_fixed_48_16_t dx, dy, a, b, off;
- linear_gradient_t *linear = (linear_gradient_t *)pict;
-
- /* reference point is the center of the pixel */
- v.vector[0] = pixman_int_to_fixed(x) + pixman_fixed_1/2;
- v.vector[1] = pixman_int_to_fixed(y) + pixman_fixed_1/2;
- v.vector[2] = pixman_fixed_1;
- if (pict->common.transform) {
- if (!pixman_transform_point_3d (pict->common.transform, &v))
- return;
- unit.vector[0] = pict->common.transform->matrix[0][0];
- unit.vector[1] = pict->common.transform->matrix[1][0];
- unit.vector[2] = pict->common.transform->matrix[2][0];
- } else {
- unit.vector[0] = pixman_fixed_1;
- unit.vector[1] = 0;
- unit.vector[2] = 0;
- }
-
- dx = linear->p2.x - linear->p1.x;
- dy = linear->p2.y - linear->p1.y;
- l = dx*dx + dy*dy;
- if (l != 0) {
- a = (dx << 32) / l;
- b = (dy << 32) / l;
- off = (-a*linear->p1.x - b*linear->p1.y)>>16;
- }
- if (l == 0 || (unit.vector[2] == 0 && v.vector[2] == pixman_fixed_1)) {
- pixman_fixed_48_16_t inc, t;
- /* affine transformation only */
- if (l == 0) {
- t = 0;
- inc = 0;
- } else {
- t = ((a*v.vector[0] + b*v.vector[1]) >> 16) + off;
- inc = (a * unit.vector[0] + b * unit.vector[1]) >> 16;
- }
-
- if (pict->class == SOURCE_IMAGE_CLASS_VERTICAL)
- {
- register uint32_t color;
-
- color = _gradient_walker_pixel( &walker, t );
- while (buffer < end)
- *(buffer++) = color;
- }
- else
- {
- if (!mask) {
- while (buffer < end)
- {
- *(buffer) = _gradient_walker_pixel (&walker, t);
- buffer += 1;
- t += inc;
- }
- } else {
- while (buffer < end) {
- if (*mask++ & maskBits)
- {
- *(buffer) = _gradient_walker_pixel (&walker, t);
- }
- buffer += 1;
- t += inc;
- }
- }
- }
- }
- else /* projective transformation */
- {
- pixman_fixed_48_16_t t;
-
- if (pict->class == SOURCE_IMAGE_CLASS_VERTICAL)
- {
- register uint32_t color;
-
- if (v.vector[2] == 0)
- {
- t = 0;
- }
- else
- {
- pixman_fixed_48_16_t x, y;
-
- x = ((pixman_fixed_48_16_t) v.vector[0] << 16) / v.vector[2];
- y = ((pixman_fixed_48_16_t) v.vector[1] << 16) / v.vector[2];
- t = ((a * x + b * y) >> 16) + off;
- }
-
- color = _gradient_walker_pixel( &walker, t );
- while (buffer < end)
- *(buffer++) = color;
- }
- else
- {
- while (buffer < end)
- {
- if (!mask || *mask++ & maskBits)
- {
- if (v.vector[2] == 0) {
- t = 0;
- } else {
- pixman_fixed_48_16_t x, y;
- x = ((pixman_fixed_48_16_t)v.vector[0] << 16) / v.vector[2];
- y = ((pixman_fixed_48_16_t)v.vector[1] << 16) / v.vector[2];
- t = ((a*x + b*y) >> 16) + off;
- }
- *(buffer) = _gradient_walker_pixel (&walker, t);
- }
- ++buffer;
- v.vector[0] += unit.vector[0];
- v.vector[1] += unit.vector[1];
- v.vector[2] += unit.vector[2];
- }
- }
- }
- } else {
-
-/*
- * In the radial gradient problem we are given two circles (c₁,r₁) and
- * (c₂,r₂) that define the gradient itself. Then, for any point p, we
- * must compute the value(s) of t within [0.0, 1.0] representing the
- * circle(s) that would color the point.
- *
- * There are potentially two values of t since the point p can be
- * colored by both sides of the circle, (which happens whenever one
- * circle is not entirely contained within the other).
- *
- * If we solve for a value of t that is outside of [0.0, 1.0] then we
- * use the extend mode (NONE, REPEAT, REFLECT, or PAD) to map to a
- * value within [0.0, 1.0].
- *
- * Here is an illustration of the problem:
- *
- * p₂
- * p •
- * • ╲
- * · ╲r₂
- * p₁ · ╲
- * • θ╲
- * ╲ ╌╌•
- * ╲r₁ · c₂
- * θ╲ ·
- * ╌╌•
- * c₁
- *
- * Given (c₁,r₁), (c₂,r₂) and p, we must find an angle θ such that two
- * points p₁ and p₂ on the two circles are collinear with p. Then, the
- * desired value of t is the ratio of the length of p₁p to the length
- * of p₁p₂.
- *
- * So, we have six unknown values: (p₁x, p₁y), (p₂x, p₂y), θ and t.
- * We can also write six equations that constrain the problem:
- *
- * Point p₁ is a distance r₁ from c₁ at an angle of θ:
- *
- * 1. p₁x = c₁x + r₁·cos θ
- * 2. p₁y = c₁y + r₁·sin θ
- *
- * Point p₂ is a distance r₂ from c₂ at an angle of θ:
- *
- * 3. p₂x = c₂x + r2·cos θ
- * 4. p₂y = c₂y + r2·sin θ
- *
- * Point p lies at a fraction t along the line segment p₁p₂:
- *
- * 5. px = t·p₂x + (1-t)·p₁x
- * 6. py = t·p₂y + (1-t)·p₁y
- *
- * To solve, first subtitute 1-4 into 5 and 6:
- *
- * px = t·(c₂x + r₂·cos θ) + (1-t)·(c₁x + r₁·cos θ)
- * py = t·(c₂y + r₂·sin θ) + (1-t)·(c₁y + r₁·sin θ)
- *
- * Then solve each for cos θ and sin θ expressed as a function of t:
- *
- * cos θ = (-(c₂x - c₁x)·t + (px - c₁x)) / ((r₂-r₁)·t + r₁)
- * sin θ = (-(c₂y - c₁y)·t + (py - c₁y)) / ((r₂-r₁)·t + r₁)
- *
- * To simplify this a bit, we define new variables for several of the
- * common terms as shown below:
- *
- * p₂
- * p •
- * • ╲
- * · ┆ ╲r₂
- * p₁ · ┆ ╲
- * • pdy┆ ╲
- * ╲ ┆ •c₂
- * ╲r₁ ┆ · ┆
- * ╲ ·┆ ┆cdy
- * •╌╌╌╌┴╌╌╌╌╌╌╌┘
- * c₁ pdx cdx
- *
- * cdx = (c₂x - c₁x)
- * cdy = (c₂y - c₁y)
- * dr = r₂-r₁
- * pdx = px - c₁x
- * pdy = py - c₁y
- *
- * Note that cdx, cdy, and dr do not depend on point p at all, so can
- * be pre-computed for the entire gradient. The simplifed equations
- * are now:
- *
- * cos θ = (-cdx·t + pdx) / (dr·t + r₁)
- * sin θ = (-cdy·t + pdy) / (dr·t + r₁)
- *
- * Finally, to get a single function of t and eliminate the last
- * unknown θ, we use the identity sin²θ + cos²θ = 1. First, square
- * each equation, (we knew a quadratic was coming since it must be
- * possible to obtain two solutions in some cases):
- *
- * cos²θ = (cdx²t² - 2·cdx·pdx·t + pdx²) / (dr²·t² + 2·r₁·dr·t + r₁²)
- * sin²θ = (cdy²t² - 2·cdy·pdy·t + pdy²) / (dr²·t² + 2·r₁·dr·t + r₁²)
- *
- * Then add both together, set the result equal to 1, and express as a
- * standard quadratic equation in t of the form At² + Bt + C = 0
- *
- * (cdx² + cdy² - dr²)·t² - 2·(cdx·pdx + cdy·pdy + r₁·dr)·t + (pdx² + pdy² - r₁²) = 0
- *
- * In other words:
- *
- * A = cdx² + cdy² - dr²
- * B = -2·(pdx·cdx + pdy·cdy + r₁·dr)
- * C = pdx² + pdy² - r₁²
- *
- * And again, notice that A does not depend on p, so can be
- * precomputed. From here we just use the quadratic formula to solve
- * for t:
- *
- * t = (-2·B ± ⎷(B² - 4·A·C)) / 2·A
- */
- /* radial or conical */
- pixman_bool_t affine = TRUE;
- double cx = 1.;
- double cy = 0.;
- double cz = 0.;
- double rx = x + 0.5;
- double ry = y + 0.5;
- double rz = 1.;
-
- if (pict->common.transform) {
- pixman_vector_t v;
- /* reference point is the center of the pixel */
- v.vector[0] = pixman_int_to_fixed(x) + pixman_fixed_1/2;
- v.vector[1] = pixman_int_to_fixed(y) + pixman_fixed_1/2;
- v.vector[2] = pixman_fixed_1;
- if (!pixman_transform_point_3d (pict->common.transform, &v))
- return;
-
- cx = pict->common.transform->matrix[0][0]/65536.;
- cy = pict->common.transform->matrix[1][0]/65536.;
- cz = pict->common.transform->matrix[2][0]/65536.;
- rx = v.vector[0]/65536.;
- ry = v.vector[1]/65536.;
- rz = v.vector[2]/65536.;
- affine = pict->common.transform->matrix[2][0] == 0 && v.vector[2] == pixman_fixed_1;
- }
-
- if (pict->common.type == RADIAL) {
- radial_gradient_t *radial = (radial_gradient_t *)pict;
- if (affine) {
- while (buffer < end) {
- if (!mask || *mask++ & maskBits)
- {
- double pdx, pdy;
- double B, C;
- double det;
- double c1x = radial->c1.x / 65536.0;
- double c1y = radial->c1.y / 65536.0;
- double r1 = radial->c1.radius / 65536.0;
- pixman_fixed_48_16_t t;
-
- pdx = rx - c1x;
- pdy = ry - c1y;
-
- B = -2 * ( pdx * radial->cdx
- + pdy * radial->cdy
- + r1 * radial->dr);
- C = (pdx * pdx + pdy * pdy - r1 * r1);
-
- det = (B * B) - (4 * radial->A * C);
- if (det < 0.0)
- det = 0.0;
-
- if (radial->A < 0)
- t = (pixman_fixed_48_16_t) ((- B - sqrt(det)) / (2.0 * radial->A) * 65536);
- else
- t = (pixman_fixed_48_16_t) ((- B + sqrt(det)) / (2.0 * radial->A) * 65536);
-
- *(buffer) = _gradient_walker_pixel (&walker, t);
- }
- ++buffer;
-
- rx += cx;
- ry += cy;
- }
- } else {
- /* projective */
- while (buffer < end) {
- if (!mask || *mask++ & maskBits)
- {
- double pdx, pdy;
- double B, C;
- double det;
- double c1x = radial->c1.x / 65536.0;
- double c1y = radial->c1.y / 65536.0;
- double r1 = radial->c1.radius / 65536.0;
- pixman_fixed_48_16_t t;
- double x, y;
-
- if (rz != 0) {
- x = rx/rz;
- y = ry/rz;
- } else {
- x = y = 0.;
- }
-
- pdx = x - c1x;
- pdy = y - c1y;
-
- B = -2 * ( pdx * radial->cdx
- + pdy * radial->cdy
- + r1 * radial->dr);
- C = (pdx * pdx + pdy * pdy - r1 * r1);
-
- det = (B * B) - (4 * radial->A * C);
- if (det < 0.0)
- det = 0.0;
-
- if (radial->A < 0)
- t = (pixman_fixed_48_16_t) ((- B - sqrt(det)) / (2.0 * radial->A) * 65536);
- else
- t = (pixman_fixed_48_16_t) ((- B + sqrt(det)) / (2.0 * radial->A) * 65536);
-
- *(buffer) = _gradient_walker_pixel (&walker, t);
- }
- ++buffer;
-
- rx += cx;
- ry += cy;
- rz += cz;
- }
- }
- } else /* SourcePictTypeConical */ {
- conical_gradient_t *conical = (conical_gradient_t *)pict;
- double a = conical->angle/(180.*65536);
- if (affine) {
- rx -= conical->center.x/65536.;
- ry -= conical->center.y/65536.;
-
- while (buffer < end) {
- double angle;
-
- if (!mask || *mask++ & maskBits)
- {
- pixman_fixed_48_16_t t;
-
- angle = atan2(ry, rx) + a;
- t = (pixman_fixed_48_16_t) (angle * (65536. / (2*M_PI)));
-
- *(buffer) = _gradient_walker_pixel (&walker, t);
- }
-
- ++buffer;
- rx += cx;
- ry += cy;
- }
- } else {
- while (buffer < end) {
- double x, y;
- double angle;
-
- if (!mask || *mask++ & maskBits)
- {
- pixman_fixed_48_16_t t;
-
- if (rz != 0) {
- x = rx/rz;
- y = ry/rz;
- } else {
- x = y = 0.;
- }
- x -= conical->center.x/65536.;
- y -= conical->center.y/65536.;
- angle = atan2(y, x) + a;
- t = (pixman_fixed_48_16_t) (angle * (65536. / (2*M_PI)));
-
- *(buffer) = _gradient_walker_pixel (&walker, t);
- }
-
- ++buffer;
- rx += cx;
- ry += cy;
- rz += cz;
- }
- }
- }
- }
-}
-
/*
* Fetch from region strategies
*/
--- /dev/null
+/*
+ *
+ * Copyright © 2000 Keith Packard, member of The XFree86 Project, Inc.
+ * 2005 Lars Knoll & Zack Rusin, Trolltech
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that
+ * copyright notice and this permission notice appear in supporting
+ * documentation, and that the name of Keith Packard not be used in
+ * advertising or publicity pertaining to distribution of the software without
+ * specific, written prior permission. Keith Packard makes no
+ * representations about the suitability of this software for any purpose. It
+ * is provided "as is" without express or implied warranty.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
+ * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
+ * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
+ * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+ * SOFTWARE.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <math.h>
+
+#include "pixman-private.h"
+
+typedef struct
+{
+ uint32_t left_ag;
+ uint32_t left_rb;
+ uint32_t right_ag;
+ uint32_t right_rb;
+ int32_t left_x;
+ int32_t right_x;
+ int32_t stepper;
+
+ pixman_gradient_stop_t *stops;
+ int num_stops;
+ unsigned int spread;
+
+ int need_reset;
+} GradientWalker;
+
+static void
+_gradient_walker_init (GradientWalker *walker,
+ gradient_t *gradient,
+ unsigned int spread)
+{
+ walker->num_stops = gradient->n_stops;
+ walker->stops = gradient->stops;
+ walker->left_x = 0;
+ walker->right_x = 0x10000;
+ walker->stepper = 0;
+ walker->left_ag = 0;
+ walker->left_rb = 0;
+ walker->right_ag = 0;
+ walker->right_rb = 0;
+ walker->spread = spread;
+
+ walker->need_reset = TRUE;
+}
+
+static void
+_gradient_walker_reset (GradientWalker *walker,
+ pixman_fixed_32_32_t pos)
+{
+ int32_t x, left_x, right_x;
+ pixman_color_t *left_c, *right_c;
+ int n, count = walker->num_stops;
+ pixman_gradient_stop_t * stops = walker->stops;
+
+ static const pixman_color_t transparent_black = { 0, 0, 0, 0 };
+
+ switch (walker->spread)
+ {
+ case PIXMAN_REPEAT_NORMAL:
+ x = (int32_t)pos & 0xFFFF;
+ for (n = 0; n < count; n++)
+ if (x < stops[n].x)
+ break;
+ if (n == 0) {
+ left_x = stops[count-1].x - 0x10000;
+ left_c = &stops[count-1].color;
+ } else {
+ left_x = stops[n-1].x;
+ left_c = &stops[n-1].color;
+ }
+
+ if (n == count) {
+ right_x = stops[0].x + 0x10000;
+ right_c = &stops[0].color;
+ } else {
+ right_x = stops[n].x;
+ right_c = &stops[n].color;
+ }
+ left_x += (pos - x);
+ right_x += (pos - x);
+ break;
+
+ case PIXMAN_REPEAT_PAD:
+ for (n = 0; n < count; n++)
+ if (pos < stops[n].x)
+ break;
+
+ if (n == 0) {
+ left_x = INT32_MIN;
+ left_c = &stops[0].color;
+ } else {
+ left_x = stops[n-1].x;
+ left_c = &stops[n-1].color;
+ }
+
+ if (n == count) {
+ right_x = INT32_MAX;
+ right_c = &stops[n-1].color;
+ } else {
+ right_x = stops[n].x;
+ right_c = &stops[n].color;
+ }
+ break;
+
+ case PIXMAN_REPEAT_REFLECT:
+ x = (int32_t)pos & 0xFFFF;
+ if ((int32_t)pos & 0x10000)
+ x = 0x10000 - x;
+ for (n = 0; n < count; n++)
+ if (x < stops[n].x)
+ break;
+
+ if (n == 0) {
+ left_x = -stops[0].x;
+ left_c = &stops[0].color;
+ } else {
+ left_x = stops[n-1].x;
+ left_c = &stops[n-1].color;
+ }
+
+ if (n == count) {
+ right_x = 0x20000 - stops[n-1].x;
+ right_c = &stops[n-1].color;
+ } else {
+ right_x = stops[n].x;
+ right_c = &stops[n].color;
+ }
+
+ if ((int32_t)pos & 0x10000) {
+ pixman_color_t *tmp_c;
+ int32_t tmp_x;
+
+ tmp_x = 0x10000 - right_x;
+ right_x = 0x10000 - left_x;
+ left_x = tmp_x;
+
+ tmp_c = right_c;
+ right_c = left_c;
+ left_c = tmp_c;
+
+ x = 0x10000 - x;
+ }
+ left_x += (pos - x);
+ right_x += (pos - x);
+ break;
+
+ default: /* RepeatNone */
+ for (n = 0; n < count; n++)
+ if (pos < stops[n].x)
+ break;
+
+ if (n == 0)
+ {
+ left_x = INT32_MIN;
+ right_x = stops[0].x;
+ left_c = right_c = (pixman_color_t*) &transparent_black;
+ }
+ else if (n == count)
+ {
+ left_x = stops[n-1].x;
+ right_x = INT32_MAX;
+ left_c = right_c = (pixman_color_t*) &transparent_black;
+ }
+ else
+ {
+ left_x = stops[n-1].x;
+ right_x = stops[n].x;
+ left_c = &stops[n-1].color;
+ right_c = &stops[n].color;
+ }
+ }
+
+ walker->left_x = left_x;
+ walker->right_x = right_x;
+ walker->left_ag = ((left_c->alpha >> 8) << 16) | (left_c->green >> 8);
+ walker->left_rb = ((left_c->red & 0xff00) << 8) | (left_c->blue >> 8);
+ walker->right_ag = ((right_c->alpha >> 8) << 16) | (right_c->green >> 8);
+ walker->right_rb = ((right_c->red & 0xff00) << 8) | (right_c->blue >> 8);
+
+ if ( walker->left_x == walker->right_x ||
+ ( walker->left_ag == walker->right_ag &&
+ walker->left_rb == walker->right_rb ) )
+ {
+ walker->stepper = 0;
+ }
+ else
+ {
+ int32_t width = right_x - left_x;
+ walker->stepper = ((1 << 24) + width/2)/width;
+ }
+
+ walker->need_reset = FALSE;
+}
+
+#define GRADIENT_WALKER_NEED_RESET(w,x) \
+ ( (w)->need_reset || (x) < (w)->left_x || (x) >= (w)->right_x)
+
+
+/* the following assumes that GRADIENT_WALKER_NEED_RESET(w,x) is FALSE */
+static uint32_t
+_gradient_walker_pixel (GradientWalker *walker,
+ pixman_fixed_32_32_t x)
+{
+ int dist, idist;
+ uint32_t t1, t2, a, color;
+
+ if (GRADIENT_WALKER_NEED_RESET (walker, x))
+ _gradient_walker_reset (walker, x);
+
+ dist = ((int)(x - walker->left_x)*walker->stepper) >> 16;
+ idist = 256 - dist;
+
+ /* combined INTERPOLATE and premultiply */
+ t1 = walker->left_rb*idist + walker->right_rb*dist;
+ t1 = (t1 >> 8) & 0xff00ff;
+
+ t2 = walker->left_ag*idist + walker->right_ag*dist;
+ t2 &= 0xff00ff00;
+
+ color = t2 & 0xff000000;
+ a = t2 >> 24;
+
+ t1 = t1*a + 0x800080;
+ t1 = (t1 + ((t1 >> 8) & 0xff00ff)) >> 8;
+
+ t2 = (t2 >> 8)*a + 0x800080;
+ t2 = (t2 + ((t2 >> 8) & 0xff00ff));
+
+ return (color | (t1 & 0xff00ff) | (t2 & 0xff00));
+}
+
+void pixmanFetchSourcePict(source_image_t * pict, int x, int y, int width,
+ uint32_t *buffer, uint32_t *mask, uint32_t maskBits)
+{
+#if 0
+ SourcePictPtr pGradient = pict->pSourcePict;
+#endif
+ GradientWalker walker;
+ uint32_t *end = buffer + width;
+ gradient_t *gradient;
+
+ if (pict->common.type == SOLID)
+ {
+ register uint32_t color = ((solid_fill_t *)pict)->color;
+
+ while (buffer < end)
+ *(buffer++) = color;
+
+ return;
+ }
+
+ gradient = (gradient_t *)pict;
+
+ _gradient_walker_init (&walker, gradient, pict->common.repeat);
+
+ if (pict->common.type == LINEAR) {
+ pixman_vector_t v, unit;
+ pixman_fixed_32_32_t l;
+ pixman_fixed_48_16_t dx, dy, a, b, off;
+ linear_gradient_t *linear = (linear_gradient_t *)pict;
+
+ /* reference point is the center of the pixel */
+ v.vector[0] = pixman_int_to_fixed(x) + pixman_fixed_1/2;
+ v.vector[1] = pixman_int_to_fixed(y) + pixman_fixed_1/2;
+ v.vector[2] = pixman_fixed_1;
+ if (pict->common.transform) {
+ if (!pixman_transform_point_3d (pict->common.transform, &v))
+ return;
+ unit.vector[0] = pict->common.transform->matrix[0][0];
+ unit.vector[1] = pict->common.transform->matrix[1][0];
+ unit.vector[2] = pict->common.transform->matrix[2][0];
+ } else {
+ unit.vector[0] = pixman_fixed_1;
+ unit.vector[1] = 0;
+ unit.vector[2] = 0;
+ }
+
+ dx = linear->p2.x - linear->p1.x;
+ dy = linear->p2.y - linear->p1.y;
+ l = dx*dx + dy*dy;
+ if (l != 0) {
+ a = (dx << 32) / l;
+ b = (dy << 32) / l;
+ off = (-a*linear->p1.x - b*linear->p1.y)>>16;
+ }
+ if (l == 0 || (unit.vector[2] == 0 && v.vector[2] == pixman_fixed_1)) {
+ pixman_fixed_48_16_t inc, t;
+ /* affine transformation only */
+ if (l == 0) {
+ t = 0;
+ inc = 0;
+ } else {
+ t = ((a*v.vector[0] + b*v.vector[1]) >> 16) + off;
+ inc = (a * unit.vector[0] + b * unit.vector[1]) >> 16;
+ }
+
+ if (pict->class == SOURCE_IMAGE_CLASS_VERTICAL)
+ {
+ register uint32_t color;
+
+ color = _gradient_walker_pixel( &walker, t );
+ while (buffer < end)
+ *(buffer++) = color;
+ }
+ else
+ {
+ if (!mask) {
+ while (buffer < end)
+ {
+ *(buffer) = _gradient_walker_pixel (&walker, t);
+ buffer += 1;
+ t += inc;
+ }
+ } else {
+ while (buffer < end) {
+ if (*mask++ & maskBits)
+ {
+ *(buffer) = _gradient_walker_pixel (&walker, t);
+ }
+ buffer += 1;
+ t += inc;
+ }
+ }
+ }
+ }
+ else /* projective transformation */
+ {
+ pixman_fixed_48_16_t t;
+
+ if (pict->class == SOURCE_IMAGE_CLASS_VERTICAL)
+ {
+ register uint32_t color;
+
+ if (v.vector[2] == 0)
+ {
+ t = 0;
+ }
+ else
+ {
+ pixman_fixed_48_16_t x, y;
+
+ x = ((pixman_fixed_48_16_t) v.vector[0] << 16) / v.vector[2];
+ y = ((pixman_fixed_48_16_t) v.vector[1] << 16) / v.vector[2];
+ t = ((a * x + b * y) >> 16) + off;
+ }
+
+ color = _gradient_walker_pixel( &walker, t );
+ while (buffer < end)
+ *(buffer++) = color;
+ }
+ else
+ {
+ while (buffer < end)
+ {
+ if (!mask || *mask++ & maskBits)
+ {
+ if (v.vector[2] == 0) {
+ t = 0;
+ } else {
+ pixman_fixed_48_16_t x, y;
+ x = ((pixman_fixed_48_16_t)v.vector[0] << 16) / v.vector[2];
+ y = ((pixman_fixed_48_16_t)v.vector[1] << 16) / v.vector[2];
+ t = ((a*x + b*y) >> 16) + off;
+ }
+ *(buffer) = _gradient_walker_pixel (&walker, t);
+ }
+ ++buffer;
+ v.vector[0] += unit.vector[0];
+ v.vector[1] += unit.vector[1];
+ v.vector[2] += unit.vector[2];
+ }
+ }
+ }
+ } else {
+
+/*
+ * In the radial gradient problem we are given two circles (c₁,r₁) and
+ * (c₂,r₂) that define the gradient itself. Then, for any point p, we
+ * must compute the value(s) of t within [0.0, 1.0] representing the
+ * circle(s) that would color the point.
+ *
+ * There are potentially two values of t since the point p can be
+ * colored by both sides of the circle, (which happens whenever one
+ * circle is not entirely contained within the other).
+ *
+ * If we solve for a value of t that is outside of [0.0, 1.0] then we
+ * use the extend mode (NONE, REPEAT, REFLECT, or PAD) to map to a
+ * value within [0.0, 1.0].
+ *
+ * Here is an illustration of the problem:
+ *
+ * p₂
+ * p •
+ * • ╲
+ * · ╲r₂
+ * p₁ · ╲
+ * • θ╲
+ * ╲ ╌╌•
+ * ╲r₁ · c₂
+ * θ╲ ·
+ * ╌╌•
+ * c₁
+ *
+ * Given (c₁,r₁), (c₂,r₂) and p, we must find an angle θ such that two
+ * points p₁ and p₂ on the two circles are collinear with p. Then, the
+ * desired value of t is the ratio of the length of p₁p to the length
+ * of p₁p₂.
+ *
+ * So, we have six unknown values: (p₁x, p₁y), (p₂x, p₂y), θ and t.
+ * We can also write six equations that constrain the problem:
+ *
+ * Point p₁ is a distance r₁ from c₁ at an angle of θ:
+ *
+ * 1. p₁x = c₁x + r₁·cos θ
+ * 2. p₁y = c₁y + r₁·sin θ
+ *
+ * Point p₂ is a distance r₂ from c₂ at an angle of θ:
+ *
+ * 3. p₂x = c₂x + r2·cos θ
+ * 4. p₂y = c₂y + r2·sin θ
+ *
+ * Point p lies at a fraction t along the line segment p₁p₂:
+ *
+ * 5. px = t·p₂x + (1-t)·p₁x
+ * 6. py = t·p₂y + (1-t)·p₁y
+ *
+ * To solve, first subtitute 1-4 into 5 and 6:
+ *
+ * px = t·(c₂x + r₂·cos θ) + (1-t)·(c₁x + r₁·cos θ)
+ * py = t·(c₂y + r₂·sin θ) + (1-t)·(c₁y + r₁·sin θ)
+ *
+ * Then solve each for cos θ and sin θ expressed as a function of t:
+ *
+ * cos θ = (-(c₂x - c₁x)·t + (px - c₁x)) / ((r₂-r₁)·t + r₁)
+ * sin θ = (-(c₂y - c₁y)·t + (py - c₁y)) / ((r₂-r₁)·t + r₁)
+ *
+ * To simplify this a bit, we define new variables for several of the
+ * common terms as shown below:
+ *
+ * p₂
+ * p •
+ * • ╲
+ * · ┆ ╲r₂
+ * p₁ · ┆ ╲
+ * • pdy┆ ╲
+ * ╲ ┆ •c₂
+ * ╲r₁ ┆ · ┆
+ * ╲ ·┆ ┆cdy
+ * •╌╌╌╌┴╌╌╌╌╌╌╌┘
+ * c₁ pdx cdx
+ *
+ * cdx = (c₂x - c₁x)
+ * cdy = (c₂y - c₁y)
+ * dr = r₂-r₁
+ * pdx = px - c₁x
+ * pdy = py - c₁y
+ *
+ * Note that cdx, cdy, and dr do not depend on point p at all, so can
+ * be pre-computed for the entire gradient. The simplifed equations
+ * are now:
+ *
+ * cos θ = (-cdx·t + pdx) / (dr·t + r₁)
+ * sin θ = (-cdy·t + pdy) / (dr·t + r₁)
+ *
+ * Finally, to get a single function of t and eliminate the last
+ * unknown θ, we use the identity sin²θ + cos²θ = 1. First, square
+ * each equation, (we knew a quadratic was coming since it must be
+ * possible to obtain two solutions in some cases):
+ *
+ * cos²θ = (cdx²t² - 2·cdx·pdx·t + pdx²) / (dr²·t² + 2·r₁·dr·t + r₁²)
+ * sin²θ = (cdy²t² - 2·cdy·pdy·t + pdy²) / (dr²·t² + 2·r₁·dr·t + r₁²)
+ *
+ * Then add both together, set the result equal to 1, and express as a
+ * standard quadratic equation in t of the form At² + Bt + C = 0
+ *
+ * (cdx² + cdy² - dr²)·t² - 2·(cdx·pdx + cdy·pdy + r₁·dr)·t + (pdx² + pdy² - r₁²) = 0
+ *
+ * In other words:
+ *
+ * A = cdx² + cdy² - dr²
+ * B = -2·(pdx·cdx + pdy·cdy + r₁·dr)
+ * C = pdx² + pdy² - r₁²
+ *
+ * And again, notice that A does not depend on p, so can be
+ * precomputed. From here we just use the quadratic formula to solve
+ * for t:
+ *
+ * t = (-2·B ± ⎷(B² - 4·A·C)) / 2·A
+ */
+ /* radial or conical */
+ pixman_bool_t affine = TRUE;
+ double cx = 1.;
+ double cy = 0.;
+ double cz = 0.;
+ double rx = x + 0.5;
+ double ry = y + 0.5;
+ double rz = 1.;
+
+ if (pict->common.transform) {
+ pixman_vector_t v;
+ /* reference point is the center of the pixel */
+ v.vector[0] = pixman_int_to_fixed(x) + pixman_fixed_1/2;
+ v.vector[1] = pixman_int_to_fixed(y) + pixman_fixed_1/2;
+ v.vector[2] = pixman_fixed_1;
+ if (!pixman_transform_point_3d (pict->common.transform, &v))
+ return;
+
+ cx = pict->common.transform->matrix[0][0]/65536.;
+ cy = pict->common.transform->matrix[1][0]/65536.;
+ cz = pict->common.transform->matrix[2][0]/65536.;
+ rx = v.vector[0]/65536.;
+ ry = v.vector[1]/65536.;
+ rz = v.vector[2]/65536.;
+ affine = pict->common.transform->matrix[2][0] == 0 && v.vector[2] == pixman_fixed_1;
+ }
+
+ if (pict->common.type == RADIAL) {
+ radial_gradient_t *radial = (radial_gradient_t *)pict;
+ if (affine) {
+ while (buffer < end) {
+ if (!mask || *mask++ & maskBits)
+ {
+ double pdx, pdy;
+ double B, C;
+ double det;
+ double c1x = radial->c1.x / 65536.0;
+ double c1y = radial->c1.y / 65536.0;
+ double r1 = radial->c1.radius / 65536.0;
+ pixman_fixed_48_16_t t;
+
+ pdx = rx - c1x;
+ pdy = ry - c1y;
+
+ B = -2 * ( pdx * radial->cdx
+ + pdy * radial->cdy
+ + r1 * radial->dr);
+ C = (pdx * pdx + pdy * pdy - r1 * r1);
+
+ det = (B * B) - (4 * radial->A * C);
+ if (det < 0.0)
+ det = 0.0;
+
+ if (radial->A < 0)
+ t = (pixman_fixed_48_16_t) ((- B - sqrt(det)) / (2.0 * radial->A) * 65536);
+ else
+ t = (pixman_fixed_48_16_t) ((- B + sqrt(det)) / (2.0 * radial->A) * 65536);
+
+ *(buffer) = _gradient_walker_pixel (&walker, t);
+ }
+ ++buffer;
+
+ rx += cx;
+ ry += cy;
+ }
+ } else {
+ /* projective */
+ while (buffer < end) {
+ if (!mask || *mask++ & maskBits)
+ {
+ double pdx, pdy;
+ double B, C;
+ double det;
+ double c1x = radial->c1.x / 65536.0;
+ double c1y = radial->c1.y / 65536.0;
+ double r1 = radial->c1.radius / 65536.0;
+ pixman_fixed_48_16_t t;
+ double x, y;
+
+ if (rz != 0) {
+ x = rx/rz;
+ y = ry/rz;
+ } else {
+ x = y = 0.;
+ }
+
+ pdx = x - c1x;
+ pdy = y - c1y;
+
+ B = -2 * ( pdx * radial->cdx
+ + pdy * radial->cdy
+ + r1 * radial->dr);
+ C = (pdx * pdx + pdy * pdy - r1 * r1);
+
+ det = (B * B) - (4 * radial->A * C);
+ if (det < 0.0)
+ det = 0.0;
+
+ if (radial->A < 0)
+ t = (pixman_fixed_48_16_t) ((- B - sqrt(det)) / (2.0 * radial->A) * 65536);
+ else
+ t = (pixman_fixed_48_16_t) ((- B + sqrt(det)) / (2.0 * radial->A) * 65536);
+
+ *(buffer) = _gradient_walker_pixel (&walker, t);
+ }
+ ++buffer;
+
+ rx += cx;
+ ry += cy;
+ rz += cz;
+ }
+ }
+ } else /* SourcePictTypeConical */ {
+ conical_gradient_t *conical = (conical_gradient_t *)pict;
+ double a = conical->angle/(180.*65536);
+ if (affine) {
+ rx -= conical->center.x/65536.;
+ ry -= conical->center.y/65536.;
+
+ while (buffer < end) {
+ double angle;
+
+ if (!mask || *mask++ & maskBits)
+ {
+ pixman_fixed_48_16_t t;
+
+ angle = atan2(ry, rx) + a;
+ t = (pixman_fixed_48_16_t) (angle * (65536. / (2*M_PI)));
+
+ *(buffer) = _gradient_walker_pixel (&walker, t);
+ }
+
+ ++buffer;
+ rx += cx;
+ ry += cy;
+ }
+ } else {
+ while (buffer < end) {
+ double x, y;
+ double angle;
+
+ if (!mask || *mask++ & maskBits)
+ {
+ pixman_fixed_48_16_t t;
+
+ if (rz != 0) {
+ x = rx/rz;
+ y = ry/rz;
+ } else {
+ x = y = 0.;
+ }
+ x -= conical->center.x/65536.;
+ y -= conical->center.y/65536.;
+ angle = atan2(y, x) + a;
+ t = (pixman_fixed_48_16_t) (angle * (65536. / (2*M_PI)));
+
+ *(buffer) = _gradient_walker_pixel (&walker, t);
+ }
+
+ ++buffer;
+ rx += cx;
+ ry += cy;
+ rz += cz;
+ }
+ }
+ }
+ }
+}
projects / platform / upstream / pixman.git / commitdiff