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1
7
8 package java.awt;
9
10 import java.awt.image.Raster  ;
11 import java.awt.image.WritableRaster ;
12 import sun.awt.image.IntegerComponentRaster;
13 import java.awt.image.ColorModel ;
14 import java.awt.image.DirectColorModel ;
15 import java.awt.geom.Point2D ;
16 import java.awt.geom.AffineTransform ;
17 import java.awt.geom.NoninvertibleTransformException ;
18 import java.lang.ref.WeakReference ;
19
20 class GradientPaintContext implements PaintContext {
21 static ColorModel xrgbmodel =
22 new DirectColorModel (24, 0x00ff0000, 0x0000ff00, 0x000000ff);
23 static ColorModel xbgrmodel =
24 new DirectColorModel (24, 0x000000ff, 0x0000ff00, 0x00ff0000);
25
26 static ColorModel cachedModel;
27 static WeakReference cached;
28
29 static synchronized Raster getCachedRaster(ColorModel cm, int w, int h) {
30 if (cm == cachedModel) {
31 if (cached != null) {
32 Raster ras = (Raster ) cached.get();
33 if (ras != null &&
34 ras.getWidth() >= w &&
35 ras.getHeight() >= h)
36 {
37 cached = null;
38 return ras;
39 }
40 }
41 }
42 return cm.createCompatibleWritableRaster(w, h);
43 }
44
45 static synchronized void putCachedRaster(ColorModel cm, Raster ras) {
46 if (cached != null) {
47 Raster cras = (Raster ) cached.get();
48 if (cras != null) {
49 int cw = cras.getWidth();
50 int ch = cras.getHeight();
51 int iw = ras.getWidth();
52 int ih = ras.getHeight();
53 if (cw >= iw && ch >= ih) {
54 return;
55 }
56 if (cw * ch >= iw * ih) {
57 return;
58 }
59 }
60 }
61 cachedModel = cm;
62 cached = new WeakReference (ras);
63 }
64
65 double x1;
66 double y1;
67 double dx;
68 double dy;
69 boolean cyclic;
70 int interp[];
71 Raster saved;
72 ColorModel model;
73
74 public GradientPaintContext(ColorModel cm,
75 Point2D p1, Point2D p2, AffineTransform xform,
76 Color c1, Color c2, boolean cyclic) {
77 Point2D xvec = new Point2D.Double (1, 0);
80 Point2D yvec = new Point2D.Double (0, 1);
81 try {
82 AffineTransform inverse = xform.createInverse();
83 inverse.deltaTransform(xvec, xvec);
84 inverse.deltaTransform(yvec, yvec);
85 } catch (NoninvertibleTransformException e) {
86 xvec.setLocation(0, 0);
87 yvec.setLocation(0, 0);
88 }
89
90 double udx = p2.getX() - p1.getX();
94 double udy = p2.getY() - p1.getY();
95 double ulenSq = udx * udx + udy * udy;
96
97 if (ulenSq <= Double.MIN_VALUE) {
98 dx = 0;
99 dy = 0;
100 } else {
101 dx = (xvec.getX() * udx + xvec.getY() * udy) / ulenSq;
117 dy = (yvec.getX() * udx + yvec.getY() * udy) / ulenSq;
118
119 if (cyclic) {
120 dx = dx % 1.0;
121 dy = dy % 1.0;
122 } else {
123 if (dx < 0) {
125 Point2D p = p1; p1 = p2; p2 = p;
131 Color c = c1; c1 = c2; c2 = c;
132 dx = -dx;
133 dy = -dy;
134 }
135 }
136 }
137
138 Point2D dp1 = xform.transform(p1, null);
139 this.x1 = dp1.getX();
140 this.y1 = dp1.getY();
141
142 this.cyclic = cyclic;
143 int rgb1 = c1.getRGB();
144 int rgb2 = c2.getRGB();
145 int a1 = (rgb1 >> 24) & 0xff;
146 int r1 = (rgb1 >> 16) & 0xff;
147 int g1 = (rgb1 >> 8) & 0xff;
148 int b1 = (rgb1 ) & 0xff;
149 int da = ((rgb2 >> 24) & 0xff) - a1;
150 int dr = ((rgb2 >> 16) & 0xff) - r1;
151 int dg = ((rgb2 >> 8) & 0xff) - g1;
152 int db = ((rgb2 ) & 0xff) - b1;
153 if (a1 == 0xff && da == 0) {
154 model = xrgbmodel;
155 if (cm instanceof DirectColorModel ) {
156 DirectColorModel dcm = (DirectColorModel ) cm;
157 int tmp = dcm.getAlphaMask();
158 if ((tmp == 0 || tmp == 0xff) &&
159 dcm.getRedMask() == 0xff &&
160 dcm.getGreenMask() == 0xff00 &&
161 dcm.getBlueMask() == 0xff0000)
162 {
163 model = xbgrmodel;
164 tmp = r1; r1 = b1; b1 = tmp;
165 tmp = dr; dr = db; db = tmp;
166 }
167 }
168 } else {
169 model = ColorModel.getRGBdefault();
170 }
171 interp = new int[cyclic ? 513 : 257];
172 for (int i = 0; i <= 256; i++) {
173 float rel = i / 256.0f;
174 int rgb =
175 (((int) (a1 + da * rel)) << 24) |
176 (((int) (r1 + dr * rel)) << 16) |
177 (((int) (g1 + dg * rel)) << 8) |
178 (((int) (b1 + db * rel)) );
179 interp[i] = rgb;
180 if (cyclic) {
181 interp[512 - i] = rgb;
182 }
183 }
184 }
185
186
189 public void dispose() {
190 if (saved != null) {
191 putCachedRaster(model, saved);
192 saved = null;
193 }
194 }
195
196
199 public ColorModel getColorModel() {
200 return model;
201 }
202
203
209 public Raster getRaster(int x, int y, int w, int h) {
210 double rowrel = (x - x1) * dx + (y - y1) * dy;
211
212 Raster rast = saved;
213 if (rast == null || rast.getWidth() < w || rast.getHeight() < h) {
214 rast = getCachedRaster(model, w, h);
215 saved = rast;
216 }
217 IntegerComponentRaster irast = (IntegerComponentRaster) rast;
218 int off = irast.getDataOffset(0);
219 int adjust = irast.getScanlineStride() - w;
220 int[] pixels = irast.getDataStorage();
221
222 if (cyclic) {
223 cycleFillRaster(pixels, off, adjust, w, h, rowrel, dx, dy);
224 } else {
225 clipFillRaster(pixels, off, adjust, w, h, rowrel, dx, dy);
226 }
227
228 return rast;
229 }
230
231 void cycleFillRaster(int[] pixels, int off, int adjust, int w, int h,
232 double rowrel, double dx, double dy) {
233 rowrel = rowrel % 2.0;
234 int irowrel = ((int) (rowrel * (1 << 30))) << 1;
235 int idx = (int) (-dx * (1 << 31));
236 int idy = (int) (-dy * (1 << 31));
237 while (--h >= 0) {
238 int icolrel = irowrel;
239 for (int j = w; j > 0; j--) {
240 pixels[off++] = interp[icolrel >>> 23];
241 icolrel += idx;
242 }
243
244 off += adjust;
245 irowrel += idy;
246 }
247 }
248
249 void clipFillRaster(int[] pixels, int off, int adjust, int w, int h,
250 double rowrel, double dx, double dy) {
251 while (--h >= 0) {
252 double colrel = rowrel;
253 int j = w;
254 if (colrel <= 0.0) {
255 int rgb = interp[0];
256 do {
257 pixels[off++] = rgb;
258 colrel += dx;
259 } while (--j > 0 && colrel <= 0.0);
260 }
261 while (colrel < 1.0 && --j >= 0) {
262 pixels[off++] = interp[(int) (colrel * 256)];
263 colrel += dx;
264 }
265 if (j > 0) {
266 int rgb = interp[256];
267 do {
268 pixels[off++] = rgb;
269 } while (--j > 0);
270 }
271
272 off += adjust;
273 rowrel += dy;
274 }
275 }
276 }
277 |
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