1/*
2 * Copyright 2015 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#include "src/gpu/GrCoordTransform.h"
9#include "src/gpu/GrFragmentProcessor.h"
10#include "src/gpu/GrProcessor.h"
11#include "src/gpu/glsl/GrGLSLFragmentProcessor.h"
12#include "src/gpu/glsl/GrGLSLFragmentShaderBuilder.h"
13#include "src/gpu/glsl/GrGLSLUniformHandler.h"
14
15void GrGLSLFragmentProcessor::setData(const GrGLSLProgramDataManager& pdman,
16 const GrFragmentProcessor& processor) {
17 this->onSetData(pdman, processor);
18}
19
20SkString GrGLSLFragmentProcessor::invokeChild(int childIndex, const char* inputColor,
21 EmitArgs& args, SkSL::String skslCoords) {
22 GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
23 while (childIndex >= (int) fFunctionNames.size()) {
24 fFunctionNames.emplace_back();
25 }
26
27 // Subtle bug workaround: If an FP (this) has a child, and wishes to sample it, but does not
28 // want to *force* explicit coord sampling, then the obvious solution is to call it with
29 // invokeChild and no coords. However, if this FP is then adopted as a child of another FP that
30 // does want to sample with explicit coords, that property is propagated (recursively) to all
31 // children, and we need to supply explicit coords. So we propagate our own "_coords" (this is
32 // the name of our explicit coords parameter generated in the helper function).
33 if (args.fFp.isSampledWithExplicitCoords() && skslCoords.length() == 0) {
34 skslCoords = "_coords";
35 }
36
37 const GrFragmentProcessor& childProc = args.fFp.childProcessor(childIndex);
38
39 // Emit the child's helper function if this is the first time we've seen a call
40 if (fFunctionNames[childIndex].size() == 0) {
41 fragBuilder->onBeforeChildProcEmitCode(); // call first so mangleString is updated
42
43 TransformedCoordVars coordVars = args.fTransformedCoords.childInputs(childIndex);
44 TextureSamplers textureSamplers = args.fTexSamplers.childInputs(childIndex);
45
46 EmitArgs childArgs(fragBuilder,
47 args.fUniformHandler,
48 args.fShaderCaps,
49 childProc,
50 "_output",
51 "_input",
52 coordVars,
53 textureSamplers);
54 fFunctionNames[childIndex] =
55 fragBuilder->writeProcessorFunction(this->childProcessor(childIndex), childArgs);
56
57 fragBuilder->onAfterChildProcEmitCode();
58 }
59
60 // If the fragment processor is invoked with overridden coordinates, it must *always* be invoked
61 // with overridden coords.
62 SkASSERT(childProc.isSampledWithExplicitCoords() == !skslCoords.empty());
63
64 // Produce a string containing the call to the helper function
65 SkString result = SkStringPrintf("%s(%s", fFunctionNames[childIndex].c_str(),
66 inputColor ? inputColor : "half4(1)");
67 if (skslCoords.length()) {
68 result.appendf(", %s", skslCoords.c_str());
69 }
70 result.append(")");
71 return result;
72}
73
74//////////////////////////////////////////////////////////////////////////////
75
76GrGLSLFragmentProcessor::Iter::Iter(std::unique_ptr<GrGLSLFragmentProcessor> fps[], int cnt) {
77 for (int i = cnt - 1; i >= 0; --i) {
78 fFPStack.push_back(fps[i].get());
79 }
80}
81
82GrGLSLFragmentProcessor& GrGLSLFragmentProcessor::Iter::operator*() const {
83 return *fFPStack.back();
84}
85
86GrGLSLFragmentProcessor* GrGLSLFragmentProcessor::Iter::operator->() const {
87 return fFPStack.back();
88}
89
90GrGLSLFragmentProcessor::Iter& GrGLSLFragmentProcessor::Iter::operator++() {
91 SkASSERT(!fFPStack.empty());
92 const GrGLSLFragmentProcessor* back = fFPStack.back();
93 fFPStack.pop_back();
94 for (int i = back->numChildProcessors() - 1; i >= 0; --i) {
95 fFPStack.push_back(back->childProcessor(i));
96 }
97 return *this;
98}
99