1 /*
2  * Copyright 2016 Google Inc.
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 
8 
9 #include "GrShaderVar.h"
10 #include "GrShaderCaps.h"
11 
12 static const char* type_modifier_string(GrShaderVar::TypeModifier t) {
13     switch (t) {
14         case GrShaderVar::kNone_TypeModifier: return "";
15         case GrShaderVar::kIn_TypeModifier: return "in";
16         case GrShaderVar::kInOut_TypeModifier: return "inout";
17         case GrShaderVar::kOut_TypeModifier: return "out";
18         case GrShaderVar::kUniform_TypeModifier: return "uniform";
19     }
20     SK_ABORT("Unknown shader variable type modifier.");
21     return "";
22 }
23 
24 void GrShaderVar::setIOType(GrIOType ioType) {
25     switch (ioType) {
26         case kRW_GrIOType:
27             return;
28         case kRead_GrIOType:
29             this->addModifier("readonly");
30             return;
31         case kWrite_GrIOType:
32             this->addModifier("writeonly");
33             return;
34     }
35     SK_ABORT("Unknown io type.");
36 }
37 
38 void GrShaderVar::appendDecl(const GrShaderCaps* shaderCaps, SkString* out) const {
39     SkASSERT(kDefault_GrSLPrecision == fPrecision || GrSLTypeTemporarilyAcceptsPrecision(fType));
40     SkString layout = fLayoutQualifier;
41     if (!fLayoutQualifier.isEmpty()) {
42         out->appendf("layout(%s) ", fLayoutQualifier.c_str());
43     }
44     out->append(fExtraModifiers);
45     if (this->getTypeModifier() != kNone_TypeModifier) {
46         out->append(type_modifier_string(this->getTypeModifier()));
47         out->append(" ");
48     }
49     GrSLType effectiveType = this->getType();
50     if (shaderCaps->usesPrecisionModifiers() && GrSLTypeAcceptsPrecision(effectiveType)) {
51         // Desktop GLSL has added precision qualifiers but they don't do anything.
52         out->appendf("%s ", GrGLSLPrecisionString(fPrecision));
53     }
54     if (this->isArray()) {
55         if (this->isUnsizedArray()) {
56             out->appendf("%s %s[]",
57                          GrGLSLTypeString(shaderCaps, effectiveType),
58                          this->getName().c_str());
59         } else {
60             SkASSERT(this->getArrayCount() > 0);
61             out->appendf("%s %s[%d]",
62                          GrGLSLTypeString(shaderCaps, effectiveType),
63                          this->getName().c_str(),
64                          this->getArrayCount());
65         }
66     } else {
67         out->appendf("%s %s",
68                      GrGLSLTypeString(shaderCaps, effectiveType),
69                      this->getName().c_str());
70     }
71 }
72