1/*
2 * Copyright (c) 2003, 2006, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26#ifndef HEADLESS
27
28#include "sun_java2d_opengl_OGLMaskFill.h"
29
30#include "OGLMaskFill.h"
31#include "OGLRenderQueue.h"
32#include "OGLVertexCache.h"
33
34/**
35 * This implementation first copies the alpha tile into a texture and then
36 * maps that texture to the destination surface. This approach appears to
37 * offer the best performance despite being a two-step process.
38 *
39 * When the source paint is a Color, we can simply use the GL_MODULATE
40 * function to multiply the current color (already premultiplied with the
41 * extra alpha value from the AlphaComposite) with the alpha value from
42 * the mask texture tile. In picture form, this process looks like:
43 *
44 * A R G B
45 * primary color Pa Pr Pg Pb (modulated with...)
46 * texture unit 0 Ca Ca Ca Ca
47 * ---------------------------------------
48 * resulting color Ra Rr Rg Rb
49 *
50 * where:
51 * Px = current color (already premultiplied by extra alpha)
52 * Cx = coverage value from mask tile
53 * Rx = resulting color/alpha component
54 *
55 * When the source paint is not a Color, it means that we are rendering with
56 * a complex paint (e.g. GradientPaint, TexturePaint). In this case, we
57 * rely on the GL_ARB_multitexture extension to effectively multiply the
58 * paint fragments (autogenerated on texture unit 1, see the
59 * OGLPaints_Set{Gradient,Texture,etc}Paint() methods for more details)
60 * with the coverage values from the mask texture tile (provided on texture
61 * unit 0), all of which is multiplied with the current color value (which
62 * contains the extra alpha value). In picture form:
63 *
64 * A R G B
65 * primary color Ea Ea Ea Ea (modulated with...)
66 * texture unit 0 Ca Ca Ca Ca (modulated with...)
67 * texture unit 1 Pa Pr Pg Pb
68 * ---------------------------------------
69 * resulting color Ra Rr Rg Rb
70 *
71 * where:
72 * Ea = extra alpha
73 * Cx = coverage value from mask tile
74 * Px = gradient/texture paint color (generated for each fragment)
75 * Rx = resulting color/alpha component
76 *
77 * Here are some descriptions of the many variables used in this method:
78 * x,y - upper left corner of the tile destination
79 * w,h - width/height of the mask tile
80 * x0 - placekeeper for the original destination x location
81 * tw,th - width/height of the actual texture tile in pixels
82 * sx1,sy1 - upper left corner of the mask tile source region
83 * sx2,sy2 - lower left corner of the mask tile source region
84 * sx,sy - "current" upper left corner of the mask tile region of interest
85 */
86void
87OGLMaskFill_MaskFill(OGLContext *oglc,
88 jint x, jint y, jint w, jint h,
89 jint maskoff, jint maskscan, jint masklen,
90 unsigned char *pMask)
91{
92 J2dTraceLn(J2D_TRACE_INFO, "OGLMaskFill_MaskFill");
93
94 RETURN_IF_NULL(oglc);
95 CHECK_PREVIOUS_OP(OGL_STATE_MASK_OP);
96
97 J2dTraceLn4(J2D_TRACE_VERBOSE, " x=%d y=%d w=%d h=%d", x, y, w, h);
98 J2dTraceLn2(J2D_TRACE_VERBOSE, " maskoff=%d maskscan=%d",
99 maskoff, maskscan);
100
101 {
102 jint tw, th, x0;
103 jint sx1, sy1, sx2, sy2;
104 jint sx, sy, sw, sh;
105
106 x0 = x;
107 tw = OGLVC_MASK_CACHE_TILE_WIDTH;
108 th = OGLVC_MASK_CACHE_TILE_HEIGHT;
109 sx1 = maskoff % maskscan;
110 sy1 = maskoff / maskscan;
111 sx2 = sx1 + w;
112 sy2 = sy1 + h;
113
114 for (sy = sy1; sy < sy2; sy += th, y += th) {
115 x = x0;
116 sh = ((sy + th) > sy2) ? (sy2 - sy) : th;
117
118 for (sx = sx1; sx < sx2; sx += tw, x += tw) {
119 sw = ((sx + tw) > sx2) ? (sx2 - sx) : tw;
120
121 OGLVertexCache_AddMaskQuad(oglc,
122 sx, sy, x, y, sw, sh,
123 maskscan, pMask);
124 }
125 }
126 }
127}
128
129JNIEXPORT void JNICALL
130Java_sun_java2d_opengl_OGLMaskFill_maskFill
131 (JNIEnv *env, jobject self,
132 jint x, jint y, jint w, jint h,
133 jint maskoff, jint maskscan, jint masklen,
134 jbyteArray maskArray)
135{
136 OGLContext *oglc = OGLRenderQueue_GetCurrentContext();
137 unsigned char *mask;
138
139 J2dTraceLn(J2D_TRACE_ERROR, "OGLMaskFill_maskFill");
140
141 if (maskArray != NULL) {
142 mask = (unsigned char *)
143 (*env)->GetPrimitiveArrayCritical(env, maskArray, NULL);
144 } else {
145 mask = NULL;
146 }
147
148 OGLMaskFill_MaskFill(oglc,
149 x, y, w, h,
150 maskoff, maskscan, masklen, mask);
151
152 // 6358147: reset current state, and ensure rendering is flushed to dest
153 if (oglc != NULL) {
154 RESET_PREVIOUS_OP();
155 j2d_glFlush();
156 }
157
158 if (mask != NULL) {
159 (*env)->ReleasePrimitiveArrayCritical(env, maskArray, mask, JNI_ABORT);
160 }
161}
162
163#endif /* !HEADLESS */
164