mutter/clutter/cogl/gl/cogl-primitives.c

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/*
* Clutter COGL
*
* A basic GL/GLES Abstraction/Utility Layer
*
* Authored By Matthew Allum <mallum@openedhand.com>
*
* Copyright (C) 2007 OpenedHand
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "cogl.h"
#include "cogl-internal.h"
#include "cogl-context.h"
#include <string.h>
#include <gmodule.h>
#define _COGL_MAX_BEZ_RECURSE_DEPTH 16
void
cogl_rectangle (gint x,
gint y,
guint width,
guint height)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
cogl_enable (ctx->color_alpha < 255
? COGL_ENABLE_BLEND : 0);
GE( glRecti (x, y, x + width, y + height) );
}
void
cogl_rectanglex (ClutterFixed x,
ClutterFixed y,
ClutterFixed width,
ClutterFixed height)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
cogl_enable (ctx->color_alpha < 255
? COGL_ENABLE_BLEND : 0);
GE( glRectf (CLUTTER_FIXED_TO_FLOAT (x),
CLUTTER_FIXED_TO_FLOAT (y),
CLUTTER_FIXED_TO_FLOAT (x + width),
CLUTTER_FIXED_TO_FLOAT (y + height)) );
}
#if 0
void
cogl_trapezoid (gint y1,
gint x11,
gint x21,
gint y2,
gint x12,
gint x22)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
cogl_enable (ctx->color_alpha < 255
? COGL_ENABLE_BLEND : 0);
GE( glBegin (GL_QUADS) );
GE( glVertex2i (x11, y1) );
GE( glVertex2i (x21, y1) );
GE( glVertex2i (x22, y2) );
GE( glVertex2i (x12, y2) );
GE( glEnd () );
}
void
cogl_trapezoidx (ClutterFixed y1,
ClutterFixed x11,
ClutterFixed x21,
ClutterFixed y2,
ClutterFixed x12,
ClutterFixed x22)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
cogl_enable (ctx->color_alpha < 255
? COGL_ENABLE_BLEND : 0);
GE( glBegin (GL_QUADS) );
GE( glVertex2f (CLUTTER_FIXED_TO_FLOAT (x11),
CLUTTER_FIXED_TO_FLOAT (y1)) );
GE( glVertex2f (CLUTTER_FIXED_TO_FLOAT (x21),
CLUTTER_FIXED_TO_FLOAT (y1)) );
GE( glVertex2f (CLUTTER_FIXED_TO_FLOAT (x22),
CLUTTER_FIXED_TO_FLOAT (y2)) );
GE( glVertex2f (CLUTTER_FIXED_TO_FLOAT (x12),
CLUTTER_FIXED_TO_FLOAT (y2)) );
GE( glEnd () );
}
#endif
static void
_cogl_path_clear_nodes ()
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
if (ctx->path_nodes)
g_free(ctx->path_nodes);
ctx->path_nodes = (CoglFloatVec2*) g_malloc (2 * sizeof(CoglFloatVec2));
ctx->path_nodes_size = 0;
ctx->path_nodes_cap = 2;
}
static void
_cogl_path_add_node (ClutterFixed x,
ClutterFixed y)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
CoglFloatVec2 *new_nodes = NULL;
if (ctx->path_nodes_size == ctx->path_nodes_cap)
{
new_nodes = g_realloc (ctx->path_nodes,
2 * ctx->path_nodes_cap
* sizeof (CoglFloatVec2));
if (new_nodes == NULL) return;
ctx->path_nodes = new_nodes;
ctx->path_nodes_cap *= 2;
}
ctx->path_nodes [ctx->path_nodes_size] .x = CLUTTER_FIXED_TO_FLOAT (x);
ctx->path_nodes [ctx->path_nodes_size] .y = CLUTTER_FIXED_TO_FLOAT (y);
ctx->path_nodes_size++;
if (ctx->path_nodes_size == 1)
{
ctx->path_nodes_min.x = ctx->path_nodes_max.x = x;
ctx->path_nodes_min.y = ctx->path_nodes_max.y = y;
}
else
{
if (x < ctx->path_nodes_min.x) ctx->path_nodes_min.x = x;
if (x > ctx->path_nodes_max.x) ctx->path_nodes_max.x = x;
if (y < ctx->path_nodes_min.y) ctx->path_nodes_min.y = y;
if (y > ctx->path_nodes_max.y) ctx->path_nodes_max.y = y;
}
}
static void
_cogl_path_stroke_nodes ()
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
cogl_enable (COGL_ENABLE_VERTEX_ARRAY
| (ctx->color_alpha < 255
? COGL_ENABLE_BLEND : 0));
GE( glVertexPointer (2, GL_FLOAT, 0, ctx->path_nodes) );
GE( glDrawArrays (GL_LINE_STRIP, 0, ctx->path_nodes_size) );
}
static void
_cogl_path_fill_nodes ()
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
guint bounds_x;
guint bounds_y;
guint bounds_w;
guint bounds_h;
GE( glClear (GL_STENCIL_BUFFER_BIT) );
GE( glEnable (GL_STENCIL_TEST) );
GE( glStencilFunc (GL_ALWAYS, 0x0, 0x0) );
GE( glStencilOp (GL_INVERT, GL_INVERT, GL_INVERT) );
GE( glColorMask (GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE) );
cogl_enable (COGL_ENABLE_VERTEX_ARRAY
| (ctx->color_alpha < 255 ? COGL_ENABLE_BLEND : 0));
GE( glVertexPointer (2, GL_FLOAT, 0, ctx->path_nodes) );
GE( glDrawArrays (GL_TRIANGLE_FAN, 0, ctx->path_nodes_size) );
GE( glStencilFunc (GL_EQUAL, 0x1, 0x1) );
GE( glStencilOp (GL_ZERO, GL_ZERO, GL_ZERO) );
GE( glColorMask (GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE) );
bounds_x = CLUTTER_FIXED_FLOOR (ctx->path_nodes_min.x);
bounds_y = CLUTTER_FIXED_FLOOR (ctx->path_nodes_min.y);
bounds_w = CLUTTER_FIXED_CEIL (ctx->path_nodes_max.x - ctx->path_nodes_min.x);
bounds_h = CLUTTER_FIXED_CEIL (ctx->path_nodes_max.y - ctx->path_nodes_min.y);
cogl_rectangle (bounds_x, bounds_y, bounds_w, bounds_h);
GE( glDisable (GL_STENCIL_TEST) );
}
void
cogl_fill ()
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
if (ctx->path_nodes_size == 0)
return;
_cogl_path_fill_nodes();
}
void
cogl_stroke ()
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
if (ctx->path_nodes_size == 0)
return;
_cogl_path_stroke_nodes();
}
void
cogl_path_move_to (ClutterFixed x,
ClutterFixed y)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
/* FIXME: handle multiple contours maybe? */
_cogl_path_clear_nodes ();
_cogl_path_add_node (x, y);
ctx->path_start.x = x;
ctx->path_start.y = y;
ctx->path_pen = ctx->path_start;
}
void
cogl_path_rel_move_to (ClutterFixed x,
ClutterFixed y)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
cogl_path_move_to (ctx->path_pen.x + x,
ctx->path_pen.y + y);
}
void
cogl_path_line_to (ClutterFixed x,
ClutterFixed y)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
_cogl_path_add_node (x, y);
ctx->path_pen.x = x;
ctx->path_pen.y = y;
}
void
cogl_path_rel_line_to (ClutterFixed x,
ClutterFixed y)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
cogl_path_line_to (ctx->path_pen.x + x,
ctx->path_pen.y + y);
}
void
cogl_path_close ()
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
_cogl_path_add_node (ctx->path_start.x, ctx->path_start.y);
ctx->path_pen = ctx->path_start;
}
void
cogl_line (ClutterFixed x1,
ClutterFixed y1,
ClutterFixed x2,
ClutterFixed y2)
{
cogl_path_move_to (x1, y1);
cogl_path_line_to (x2, y2);
}
void
cogl_polyline (ClutterFixed *coords,
gint num_points)
{
gint c = 0;
cogl_path_move_to (coords[0], coords[1]);
for (c = 1; c < num_points; ++c)
cogl_path_line_to (coords[2*c], coords[2*c+1]);
}
void
cogl_polygon (ClutterFixed *coords,
gint num_points)
{
cogl_polyline (coords, num_points);
cogl_path_close ();
}
void
cogl_path_rectangle (ClutterFixed x,
ClutterFixed y,
ClutterFixed width,
ClutterFixed height)
{
cogl_path_move_to (x, y);
cogl_path_line_to (x + width, y);
cogl_path_line_to (x + width, y + height);
cogl_path_line_to (x, y + height);
cogl_path_close ();
}
static void
_cogl_arc (ClutterFixed center_x,
ClutterFixed center_y,
ClutterFixed radius_x,
ClutterFixed radius_y,
ClutterAngle angle_1,
ClutterAngle angle_2,
ClutterAngle angle_step,
guint move_first)
{
ClutterAngle a = 0x0;
ClutterAngle temp = 0x0;
ClutterFixed cosa = 0x0;
ClutterFixed sina = 0x0;
ClutterFixed px = 0x0;
ClutterFixed py = 0x0;
/* Fix invalid angles */
if (angle_1 == angle_2 || angle_step == 0x0)
return;
if (angle_step < 0x0)
angle_step = -angle_step;
if (angle_2 < angle_1)
{
temp = angle_1;
angle_1 = angle_2;
angle_2 = temp;
}
/* Walk the arc by given step */
for (a = angle_1; a < angle_2; a += angle_step)
{
cosa = clutter_cosi (a);
sina = clutter_sini (a);
px = center_x + CFX_MUL (cosa, radius_x);
py = center_y + CFX_MUL (sina, radius_y);
if (a == angle_1 && move_first)
cogl_path_move_to (px, py);
else
cogl_path_line_to (px, py);
}
}
void
cogl_path_arc (ClutterFixed center_x,
ClutterFixed center_y,
ClutterFixed radius_x,
ClutterFixed radius_y,
ClutterAngle angle_1,
ClutterAngle angle_2)
{
ClutterAngle angle_step = 10;
_cogl_arc (center_x, center_y,
radius_x, radius_y,
angle_1, angle_2,
angle_step, 0 /* no move */);
}
void
cogl_path_arc_rel (ClutterFixed center_x,
ClutterFixed center_y,
ClutterFixed radius_x,
ClutterFixed radius_y,
ClutterAngle angle_1,
ClutterAngle angle_2,
ClutterAngle angle_step)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
_cogl_arc (ctx->path_pen.x + center_x,
ctx->path_pen.y + center_y,
radius_x, radius_y,
angle_1, angle_2,
angle_step, 0 /* no move */);
}
void
cogl_arc (ClutterFixed center_x,
ClutterFixed center_y,
ClutterFixed radius_x,
ClutterFixed radius_y,
ClutterAngle angle_1,
ClutterAngle angle_2)
{
ClutterAngle angle_step = 10;
_cogl_arc (center_x, center_y,
radius_x, radius_y,
angle_1, angle_2,
angle_step, 1 /* move first */);
}
void
cogl_ellipse (ClutterFixed center_x,
ClutterFixed center_y,
ClutterFixed radius_x,
ClutterFixed radius_y)
{
ClutterAngle angle_step = 10;
/* FIXME: if shows to be slow might be optimized
* by mirroring just a quarter of it */
_cogl_arc (center_x, center_y,
radius_x, radius_y,
0, CLUTTER_ANGLE_FROM_DEG(360),
angle_step, 1 /* move first */);
cogl_path_close();
}
void
cogl_round_rectangle (ClutterFixed x,
ClutterFixed y,
ClutterFixed width,
ClutterFixed height,
ClutterFixed radius,
ClutterAngle arc_step)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
ClutterFixed inner_width = width - (radius << 1);
ClutterFixed inner_height = height - (radius << 1);
cogl_path_move_to (x, y + radius);
cogl_path_arc_rel (radius, 0,
radius, radius,
CLUTTER_ANGLE_FROM_DEG (180),
CLUTTER_ANGLE_FROM_DEG (270),
arc_step);
cogl_path_line_to (ctx->path_pen.x + inner_width,
ctx->path_pen.y);
cogl_path_arc_rel (0, radius,
radius, radius,
CLUTTER_ANGLE_FROM_DEG (-90),
CLUTTER_ANGLE_FROM_DEG (0),
arc_step);
cogl_path_line_to (ctx->path_pen.x,
ctx->path_pen.y + inner_height);
cogl_path_arc_rel (-radius, 0,
radius, radius,
CLUTTER_ANGLE_FROM_DEG (0),
CLUTTER_ANGLE_FROM_DEG (90),
arc_step);
cogl_path_line_to (ctx->path_pen.x - inner_width,
ctx->path_pen.y);
cogl_path_arc_rel (0, -radius,
radius, radius,
CLUTTER_ANGLE_FROM_DEG (90),
CLUTTER_ANGLE_FROM_DEG (180),
arc_step);
cogl_path_close ();
}
#if 0
static void
_cogl_path_bezier2_sub (CoglBezQuad *quad)
{
CoglBezQuad quads[_COGL_MAX_BEZ_RECURSE_DEPTH];
CoglBezQuad *qleft;
CoglBezQuad *qright;
CoglBezQuad *q;
CoglFixedVec2 mid;
CoglFixedVec2 dif;
CoglFixedVec2 c1;
CoglFixedVec2 c2;
CoglFixedVec2 c3;
gint qindex;
/* Put first curve on stack */
quads[0] = *quad;
qindex = 0;
/* While stack is not empty */
while (qindex >= 0)
{
q = &quads[qindex];
/* Calculate distance of control point from its
* counterpart on the line between end points */
mid.x = ((q->p1.x + q->p3.x) >> 1);
mid.y = ((q->p1.y + q->p3.y) >> 1);
dif.x = (q->p2.x - mid.x);
dif.y = (q->p2.y - mid.y);
if (dif.x < 0) dif.x = -dif.x;
if (dif.y < 0) dif.y = -dif.y;
/* Cancel if the curve is flat enough */
if (dif.x + dif.y <= CFX_ONE
|| qindex == _COGL_MAX_BEZ_RECURSE_DEPTH - 1)
{
/* Add subdivision point (skip last) */
if (qindex == 0) return;
_cogl_path_add_node (q->p3.x, q->p3.y);
--qindex; continue;
}
/* Left recursion goes on top of stack! */
qright = q; qleft = &quads[++qindex];
/* Subdivide into 2 sub-curves */
c1.x = ((q->p1.x + q->p2.x) >> 1);
c1.y = ((q->p1.y + q->p2.y) >> 1);
c3.x = ((q->p2.x + q->p3.x) >> 1);
c3.y = ((q->p2.y + q->p3.y) >> 1);
c2.x = ((c1.x + c3.x) >> 1);
c2.y = ((c1.y + c3.y) >> 1);
/* Add left recursion onto stack */
qleft->p1 = q->p1;
qleft->p2 = c1;
qleft->p3 = c2;
/* Add right recursion onto stack */
qright->p1 = c2;
qright->p2 = c3;
qright->p3 = q->p3;
}
}
#endif
static void
_cogl_path_bezier3_sub (CoglBezCubic *cubic)
{
CoglBezCubic cubics[_COGL_MAX_BEZ_RECURSE_DEPTH];
CoglBezCubic *cleft;
CoglBezCubic *cright;
CoglBezCubic *c;
CoglFixedVec2 dif1;
CoglFixedVec2 dif2;
CoglFixedVec2 mm;
CoglFixedVec2 c1;
CoglFixedVec2 c2;
CoglFixedVec2 c3;
CoglFixedVec2 c4;
CoglFixedVec2 c5;
gint cindex;
/* Put first curve on stack */
cubics[0] = *cubic;
cindex = 0;
while (cindex >= 0)
{
c = &cubics[cindex];
#define CFX_MUL2(x) ((x) << 1)
#define CFX_MUL3(x) (((x) << 1) + (x))
#define CFX_SQ(x) CFX_MUL (x, x)
/* Calculate distance of control points from their
* counterparts on the line between end points */
dif1.x = CFX_MUL3 (c->p2.x) - CFX_MUL2 (c->p1.x) - c->p4.x;
dif1.y = CFX_MUL3 (c->p2.y) - CFX_MUL2 (c->p1.y) - c->p4.y;
dif2.x = CFX_MUL3 (c->p3.x) - CFX_MUL2 (c->p4.x) - c->p1.x;
dif2.y = CFX_MUL3 (c->p3.y) - CFX_MUL2 (c->p4.y) - c->p1.y;
if (dif1.x < 0) dif1.x = -dif1.x;
if (dif1.y < 0) dif1.y = -dif1.y;
if (dif2.x < 0) dif2.x = -dif2.x;
if (dif2.y < 0) dif2.y = -dif2.y;
#undef CFX_MUL2
#undef CFX_MUL3
#undef CFX_SQ
/* Pick the greatest of two distances */
if (dif1.x < dif2.x) dif1.x = dif2.x;
if (dif1.y < dif2.y) dif1.y = dif2.y;
/* Cancel if the curve is flat enough */
if (dif1.x + dif1.y <= CFX_ONE
|| cindex == _COGL_MAX_BEZ_RECURSE_DEPTH-1)
{
/* Add subdivision point (skip last) */
if (cindex == 0) return;
_cogl_path_add_node (c->p4.x, c->p4.y);
--cindex; continue;
}
/* Left recursion goes on top of stack! */
cright = c; cleft = &cubics[++cindex];
/* Subdivide into 2 sub-curves */
c1.x = ((c->p1.x + c->p2.x) >> 1);
c1.y = ((c->p1.y + c->p2.y) >> 1);
mm.x = ((c->p2.x + c->p3.x) >> 1);
mm.y = ((c->p2.y + c->p3.y) >> 1);
c5.x = ((c->p3.x + c->p4.x) >> 1);
c5.y = ((c->p3.y + c->p4.y) >> 1);
c2.x = ((c1.x + mm.x) >> 1);
c2.y = ((c1.y + mm.y) >> 1);
c4.x = ((mm.x + c5.x) >> 1);
c4.y = ((mm.y + c5.y) >> 1);
c3.x = ((c2.x + c4.x) >> 1);
c3.y = ((c2.y + c4.y) >> 1);
/* Add left recursion to stack */
cleft->p1 = c->p1;
cleft->p2 = c1;
cleft->p3 = c2;
cleft->p4 = c3;
/* Add right recursion to stack */
cright->p1 = c3;
cright->p2 = c4;
cright->p3 = c5;
cright->p4 = c->p4;
}
}
#if 0
void
cogl_path_bezier2_to (ClutterFixed x1,
ClutterFixed y1,
ClutterFixed x2,
ClutterFixed y2)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
CoglBezQuad quad;
/* Prepare quadratic curve */
quad.p1 = ctx->path_pen;
quad.p2.x = x1;
quad.p2.y = y1;
quad.p3.x = x2;
quad.p3.y = y2;
/* Run subdivision */
_cogl_path_bezier2_sub (&quad);
/* Add last point */
_cogl_path_add_node (quad.p3.x, quad.p3.y);
ctx->path_pen = quad.p3;
}
#endif
void
cogl_path_curve_to (ClutterFixed x1,
ClutterFixed y1,
ClutterFixed x2,
ClutterFixed y2,
ClutterFixed x3,
ClutterFixed y3)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
CoglBezCubic cubic;
/* Prepare cubic curve */
cubic.p1 = ctx->path_pen;
cubic.p2.x = x1;
cubic.p2.y = y1;
cubic.p3.x = x2;
cubic.p3.y = y2;
cubic.p4.x = x3;
cubic.p4.y = y3;
/* Run subdivision */
_cogl_path_bezier3_sub (&cubic);
/* Add last point */
_cogl_path_add_node (cubic.p4.x, cubic.p4.y);
ctx->path_pen = cubic.p4;
}
void
cogl_rel_curve_to (ClutterFixed x1,
ClutterFixed y1,
ClutterFixed x2,
ClutterFixed y2,
ClutterFixed x3,
ClutterFixed y3)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
cogl_path_curve_to (ctx->path_pen.x + x1,
ctx->path_pen.y + y2,
ctx->path_pen.x + x2,
ctx->path_pen.y + y2,
ctx->path_pen.x + x3,
ctx->path_pen.y + y3);
}