1 /*
2 * Copyright (c) 2008, 2013, 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 package com.sun.scenario.effect.compiler.backend.hw;
27
28 import java.util.HashMap;
29 import java.util.Map;
30 import com.sun.scenario.effect.compiler.JSLParser;
31 import com.sun.scenario.effect.compiler.model.Precision;
32 import com.sun.scenario.effect.compiler.tree.FuncDef;
33 import com.sun.scenario.effect.compiler.tree.ProgramUnit;
34
35 /**
36 */
37 public class ES2Backend extends GLSLBackend {
38
39 public ES2Backend(JSLParser parser, ProgramUnit program) {
40 super(parser, program);
41 }
42
43 // GLSL v1.10 no longer has gl_TexCoord*; these are now passed in
44 // from vertex shader as texCoord0/1
45 private static final Map<String, String> varMap = new HashMap<String, String>();
46 static {
47 varMap.put("pos0", "texCoord0");
48 varMap.put("pos1", "texCoord1");
49 varMap.put("color", "gl_FragColor");
50 varMap.put("jsl_vertexColor", "perVertexColor");
51 }
52
53 private static final Map<String, String> funcMap = new HashMap<String, String>();
54 static {
55 funcMap.put("sample", "texture2D");
56 funcMap.put("ddx", "dFdx");
57 funcMap.put("ddy", "dFdy");
58 funcMap.put("intcast", "int");
59 }
60
61 @Override
62 protected String getVar(String v) {
63 String s = varMap.get(v);
64 return (s != null) ? s : v;
65 }
66
67 @Override
68 protected String getFuncName(String f) {
69 String s = funcMap.get(f);
70 return (s != null) ? s : f;
71 }
72
73 @Override
74 protected String getPrecision(Precision p) {
75 return p.name();
76 }
77
78 @Override
79 public void visitFuncDef(FuncDef d) {
80 // this is a hack to help force the return value of certain Prism
81 // shader functions to have lower precision
82 String name = d.getFunction().getName();
83 if ("mask".equals(name) || "paint".equals(name)) {
84 output("lowp ");
85 }
86 super.visitFuncDef(d);
87 }
88
89 @Override
90 protected String getHeader() {
91 StringBuilder sb = new StringBuilder();
92 // For the time being we are attempting to generate fragment programs
93 // that will run on the desktop and on OpenGL ES 2.0 devices.
94 // For OpenGL ES 2.0, fragment programs are required to specify the
95 // precision for all variables. Also for ES 2.0, the default GLSL
96 // version is 1.00, so implicitly we are using "#version 100" for
97 // that case. We are not yet taking advantage of language features
98 // above (desktop GLSL) version 1.10 so we can get away with not
99 // including the #version directive here (it will implicitly be
100 // "#version 110" for the desktop case). It appears that the
101 // desktop and ES versions of the GLSL spec may continue to be
102 // developed independently (see section 10.23 in the GLSL ES spec),
103 // so if we ever need to use a higher version for one case or the
104 // other, it will get awkward since the #version string has to be
105 // the first thing in the file (i.e., you can't put it inside the
106 // "#ifdef GL_ES" section).
107 // TODO: We are currently using highp across the board if it is
108 // supported just to be safe, but there are likely many variables
109 // that could live with mediump or lowp; should experiment with
110 // using lower precision by default...
111 sb.append("#ifdef GL_ES\n");
112 sb.append("#extension GL_OES_standard_derivatives : enable\n");
113 sb.append("#ifdef GL_FRAGMENT_PRECISION_HIGH\n");
114 sb.append("precision highp float;\n");
115 sb.append("precision highp int;\n");
116 sb.append("#else\n");
117 sb.append("precision mediump float;\n");
118 sb.append("precision mediump int;\n");
119 sb.append("#endif\n");
120 sb.append("#else\n");
121 sb.append("#define highp\n");
122 sb.append("#define mediump\n");
123 sb.append("#define lowp\n");
124 sb.append("#endif\n");
125
126 // output varying value declarations (passed from the vertex shader)
127 if (maxTexCoordIndex >= 0) {
128 sb.append("varying vec2 texCoord0;\n");
129 }
130 if (maxTexCoordIndex >= 1) {
131 sb.append("varying vec2 texCoord1;\n");
132 }
133 if (isVertexColorReferenced) {
134 sb.append("varying lowp vec4 perVertexColor;\n");
135 }
136
137 // output special pixcoord offset uniform variable declaration
138 // at the top of the program, if needed
139 if (isPixcoordReferenced) {
140 sb.append("uniform vec4 jsl_pixCoordOffset;\n");
141 sb.append("vec2 pixcoord = vec2(\n");
142 sb.append(" gl_FragCoord.x-jsl_pixCoordOffset.x,\n");
143 sb.append(" ((jsl_pixCoordOffset.z-gl_FragCoord.y)*jsl_pixCoordOffset.w)-jsl_pixCoordOffset.y);\n");
144 }
145
146 return sb.toString();
147 }
148 }