wine/dlls/gdiplus/graphics.c
2007-06-20 13:10:24 +02:00

313 lines
8.4 KiB
C

/*
* Copyright (C) 2007 Google (Evan Stade)
*
* 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 2.1 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
*/
#include <stdarg.h>
#include <math.h>
#include "windef.h"
#include "winbase.h"
#include "winuser.h"
#include "wingdi.h"
#include "gdiplus.h"
#include "gdiplus_private.h"
#include "wine/debug.h"
/* looks-right constant */
#define TENSION_CONST (0.3)
static inline INT roundr(REAL x)
{
return (INT) floor(x+0.5);
}
static inline REAL deg2rad(REAL degrees)
{
return (M_PI*2.0) * degrees / 360.0;
}
/* Converts angle (in degrees) to x/y coordinates */
static void deg2xy(REAL angle, REAL x_0, REAL y_0, REAL *x, REAL *y)
{
REAL radAngle, hypotenuse;
radAngle = deg2rad(angle);
hypotenuse = 50.0; /* arbitrary */
*x = x_0 + cos(radAngle) * hypotenuse;
*y = y_0 + sin(radAngle) * hypotenuse;
}
/* GdipDrawPie/GdipFillPie helper function */
static GpStatus draw_pie(GpGraphics *graphics, HBRUSH gdibrush, HPEN gdipen,
REAL x, REAL y, REAL width, REAL height, REAL startAngle, REAL sweepAngle)
{
HGDIOBJ old_pen, old_brush;
REAL x_0, y_0, x_1, y_1, x_2, y_2;
if(!graphics)
return InvalidParameter;
old_pen = SelectObject(graphics->hdc, gdipen);
old_brush = SelectObject(graphics->hdc, gdibrush);
x_0 = x + (width/2.0);
y_0 = y + (height/2.0);
deg2xy(startAngle+sweepAngle, x_0, y_0, &x_1, &y_1);
deg2xy(startAngle, x_0, y_0, &x_2, &y_2);
Pie(graphics->hdc, roundr(x), roundr(y), roundr(x+width), roundr(y+height),
roundr(x_1), roundr(y_1), roundr(x_2), roundr(y_2));
SelectObject(graphics->hdc, old_pen);
SelectObject(graphics->hdc, old_brush);
return Ok;
}
/* GdipDrawCurve helper function.
* Calculates Bezier points from cardinal spline points. */
static void calc_curve_bezier(CONST GpPointF *pts, REAL tension, REAL *x1,
REAL *y1, REAL *x2, REAL *y2)
{
REAL xdiff, ydiff;
/* calculate tangent */
xdiff = pts[2].X - pts[0].X;
ydiff = pts[2].Y - pts[0].Y;
/* apply tangent to get control points */
*x1 = pts[1].X - tension * xdiff;
*y1 = pts[1].Y - tension * ydiff;
*x2 = pts[1].X + tension * xdiff;
*y2 = pts[1].Y + tension * ydiff;
}
/* GdipDrawCurve helper function.
* Calculates Bezier points from cardinal spline endpoints. */
static void calc_curve_bezier_endp(REAL xend, REAL yend, REAL xadj, REAL yadj,
REAL tension, REAL *x, REAL *y)
{
/* tangent at endpoints is the line from the endpoint to the adjacent point */
*x = roundr(tension * (xadj - xend) + xend);
*y = roundr(tension * (yadj - yend) + yend);
}
GpStatus WINGDIPAPI GdipCreateFromHDC(HDC hdc, GpGraphics **graphics)
{
if(hdc == NULL)
return OutOfMemory;
if(graphics == NULL)
return InvalidParameter;
*graphics = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY,
sizeof(GpGraphics));
(*graphics)->hdc = hdc;
(*graphics)->hwnd = NULL;
return Ok;
}
GpStatus WINGDIPAPI GdipCreateFromHWND(HWND hwnd, GpGraphics **graphics)
{
GpStatus ret;
if((ret = GdipCreateFromHDC(GetDC(hwnd), graphics)) != Ok)
return ret;
(*graphics)->hwnd = hwnd;
return Ok;
}
GpStatus WINGDIPAPI GdipDeleteGraphics(GpGraphics *graphics)
{
if(!graphics) return InvalidParameter;
if(graphics->hwnd)
ReleaseDC(graphics->hwnd, graphics->hdc);
HeapFree(GetProcessHeap(), 0, graphics);
return Ok;
}
GpStatus WINGDIPAPI GdipDrawArc(GpGraphics *graphics, GpPen *pen, REAL x,
REAL y, REAL width, REAL height, REAL startAngle, REAL sweepAngle)
{
HGDIOBJ old_pen;
REAL x_0, y_0, x_1, y_1, x_2, y_2;
if(!graphics || !pen)
return InvalidParameter;
old_pen = SelectObject(graphics->hdc, pen->gdipen);
x_0 = x + (width/2.0);
y_0 = y + (height/2.0);
deg2xy(startAngle+sweepAngle, x_0, y_0, &x_1, &y_1);
deg2xy(startAngle, x_0, y_0, &x_2, &y_2);
Arc(graphics->hdc, roundr(x), roundr(y), roundr(x+width), roundr(y+height),
roundr(x_1), roundr(y_1), roundr(x_2), roundr(y_2));
SelectObject(graphics->hdc, old_pen);
return Ok;
}
GpStatus WINGDIPAPI GdipDrawBezier(GpGraphics *graphics, GpPen *pen, REAL x1,
REAL y1, REAL x2, REAL y2, REAL x3, REAL y3, REAL x4, REAL y4)
{
HGDIOBJ old_pen;
POINT pt[4] = {{roundr(x1), roundr(y1)}, {roundr(x2), roundr(y2)},
{roundr(x3), roundr(y3)}, {roundr(x4), roundr(y4)}};
if(!graphics || !pen)
return InvalidParameter;
old_pen = SelectObject(graphics->hdc, pen->gdipen);
PolyBezier(graphics->hdc, pt, 4);
SelectObject(graphics->hdc, old_pen);
return Ok;
}
/* Approximates cardinal spline with Bezier curves. */
GpStatus WINGDIPAPI GdipDrawCurve2(GpGraphics *graphics, GpPen *pen,
GDIPCONST GpPointF *points, INT count, REAL tension)
{
HGDIOBJ old_pen;
/* PolyBezier expects count*3-2 points. */
int i, len_pt = count*3-2;
POINT pt[len_pt];
REAL x1, x2, y1, y2;
if(!graphics || !pen)
return InvalidParameter;
tension = tension * TENSION_CONST;
calc_curve_bezier_endp(points[0].X, points[0].Y, points[1].X, points[1].Y,
tension, &x1, &y1);
pt[0].x = roundr(points[0].X);
pt[0].y = roundr(points[0].Y);
pt[1].x = roundr(x1);
pt[1].y = roundr(y1);
for(i = 0; i < count-2; i++){
calc_curve_bezier(&(points[i]), tension, &x1, &y1, &x2, &y2);
pt[3*i+2].x = roundr(x1);
pt[3*i+2].y = roundr(y1);
pt[3*i+3].x = roundr(points[i+1].X);
pt[3*i+3].y = roundr(points[i+1].Y);
pt[3*i+4].x = roundr(x2);
pt[3*i+4].y = roundr(y2);
}
calc_curve_bezier_endp(points[count-1].X, points[count-1].Y,
points[count-2].X, points[count-2].Y, tension, &x1, &y1);
pt[len_pt-2].x = x1;
pt[len_pt-2].y = y1;
pt[len_pt-1].x = roundr(points[count-1].X);
pt[len_pt-1].y = roundr(points[count-1].Y);
old_pen = SelectObject(graphics->hdc, pen->gdipen);
PolyBezier(graphics->hdc, pt, len_pt);
SelectObject(graphics->hdc, old_pen);
return Ok;
}
GpStatus WINGDIPAPI GdipDrawLineI(GpGraphics *graphics, GpPen *pen, INT x1,
INT y1, INT x2, INT y2)
{
HGDIOBJ old_obj;
if(!pen || !graphics)
return InvalidParameter;
old_obj = SelectObject(graphics->hdc, pen->gdipen);
MoveToEx(graphics->hdc, x1, y1, NULL);
LineTo(graphics->hdc, x2, y2);
SelectObject(graphics->hdc, old_obj);
return Ok;
}
GpStatus WINGDIPAPI GdipDrawPie(GpGraphics *graphics, GpPen *pen, REAL x,
REAL y, REAL width, REAL height, REAL startAngle, REAL sweepAngle)
{
if(!pen)
return InvalidParameter;
return draw_pie(graphics, GetStockObject(NULL_BRUSH), pen->gdipen, x, y,
width, height, startAngle, sweepAngle);
}
GpStatus WINGDIPAPI GdipDrawRectangleI(GpGraphics *graphics, GpPen *pen, INT x,
INT y, INT width, INT height)
{
LOGBRUSH lb;
HPEN hpen;
HGDIOBJ old_obj;
if(!pen || !graphics)
return InvalidParameter;
lb.lbStyle = BS_SOLID;
lb.lbColor = pen->color;
lb.lbHatch = 0;
hpen = ExtCreatePen(PS_GEOMETRIC | PS_ENDCAP_SQUARE, (INT) pen->width,
&lb, 0, NULL);
old_obj = SelectObject(graphics->hdc, hpen);
/* assume pen aligment centered */
MoveToEx(graphics->hdc, x, y, NULL);
LineTo(graphics->hdc, x+width, y);
LineTo(graphics->hdc, x+width, y+height);
LineTo(graphics->hdc, x, y+height);
LineTo(graphics->hdc, x, y);
SelectObject(graphics->hdc, old_obj);
DeleteObject(hpen);
return Ok;
}
GpStatus WINGDIPAPI GdipFillPie(GpGraphics *graphics, GpBrush *brush, REAL x,
REAL y, REAL width, REAL height, REAL startAngle, REAL sweepAngle)
{
if(!brush)
return InvalidParameter;
return draw_pie(graphics, brush->gdibrush, GetStockObject(NULL_PEN), x, y,
width, height, startAngle, sweepAngle);
}