Initial refactor of shaderbuilder

src/gpu/gl/GrGLSLPrettyPrint.cpp

-/*
- * Copyright 2014 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-#include "gl/GrGLSLPrettyPrint.h"
-
-namespace GrGLSLPrettyPrint {
-
-class GLSLPrettyPrint {
-public:
-    GLSLPrettyPrint() {}
-
-    SkString prettify(const SkString& input, bool countlines) {
-        // setup pretty state
-        fIndex = 0;
-        fLength = input.size();
-        fInput = input;
-        fCountlines = countlines;
-        fTabs = 0;
-        fLinecount = 1;
-        fFreshline = true;
-
-        int parensDepth = 0;
-        // number 1st line
-        this->lineNumbering();
-        while (fLength > fIndex) {
-            /* the heart and soul of our prettification algorithm.  The rules should hopefully be
-             * self explanatory.  For '#' and '//' tokens we parse until we reach a newline.
-             *
-             * For long style comments like this one, we search for the ending token.  We also
-             * preserve whitespace in these comments WITH THE CAVEAT that we do the newlines
-             * ourselves.  This allows us to remain in control of line numbers, and matching tabs
-             * Existing tabs in the input string are copied over too, but this will look funny
-             *
-             * '{' and '}' are handled in basically the same way.  We add a newline if we aren't
-             * on a fresh line, dirty the line, then add a second newline, ie braces are always
-             * on their own lines indented properly.  The one funkiness here is structs print with
-             * the semicolon on its own line.  Its not a problem for a glsl compiler though
-             *
-             * '(' and ')' are basically ignored, except as a sign we need to ignore ';' ala
-             * in for loops.
-             *
-             * ';' means add a new line
-             *
-             * '\t' and '\n' are ignored in general parsing for backwards compatability with
-             * existing shader code and we also have a special case for handling whitespace
-             * at the beginning of fresh lines.
-             *
-             * Otherwise just add the new character to the pretty string, indenting if necessary.
-             */
-            if (this->hasToken("#") || this->hasToken("//")) {
-                this->parseUntilNewline();
-            } else if (this->hasToken("/*")) {
-                this->parseUntil("*/");
-            } else if ('{' == fInput[fIndex]) {
-                this->newline();
-                this->appendChar('{');
-                fTabs++;
-                this->newline();
-            } else if ('}' == fInput[fIndex]) {
-                fTabs--;
-                this->newline();
-                this->appendChar('}');
-                this->newline();
-            } else if (this->hasToken(")")) {
-                parensDepth--;
-            } else if (this->hasToken("(")) {
-                parensDepth++;
-            } else if (!parensDepth && this->hasToken(";")) {
-                this->newline();
-            } else if ('\t' == fInput[fIndex] || '\n' == fInput[fIndex] ||
-                    (fFreshline && ' ' == fInput[fIndex])) {
-                fIndex++;
-            } else {
-                this->appendChar(input[fIndex]);
-            }
-        }
-        return fPretty;
-    }
-private:
-    void appendChar(char c) {
-        this->tabString();
-        fPretty.appendf("%c", fInput[fIndex++]);
-        fFreshline = false;
-    }
-
-    // hasToken automatically consumes the next token, if it is a match, and then tabs
-    // if necessary, before inserting the token into the pretty string
-    bool hasToken(const char* token) {
-        size_t i = fIndex;
-        for (size_t j = 0; token[j] && fLength > i; i++, j++) {
-            if (token[j] != fInput[i]) {
-                return false;
-            }
-        }
-        this->tabString();
-        fIndex = i;
-        fPretty.append(token);
-        fFreshline = false;
-        return true;
-    }
-
-    void parseUntilNewline() {
-        while (fLength > fIndex) {
-            if ('\n' == fInput[fIndex]) {
-                fIndex++;
-                this->newline();
-                break;
-            }
-            fPretty.appendf("%c", fInput[fIndex++]);
-        }
-    }
-
-    // this code assumes it is not actually searching for a newline.  If you need to search for a
-    // newline, then use the function above.  If you do search for a newline with this function
-    // it will consume the entire string and the output will certainly not be prettified
-    void parseUntil(const char* token) {
-        while (fLength > fIndex) {
-            // For embedded newlines,  this code will make sure to embed the newline in the
-            // pretty string, increase the linecount, and tab out the next line to the appropriate
-            // place
-            if ('\n' == fInput[fIndex]) {
-                this->newline();
-                this->tabString();
-                fIndex++;
-            }
-            if (this->hasToken(token)) {
-                break;
-            }
-            fFreshline = false;
-            fPretty.appendf("%c", fInput[fIndex++]);
-        }
-    }
-
-    // We only tab if on a newline, otherwise consider the line tabbed
-    void tabString() {
-        if (fFreshline) {
-            for (int t = 0; t < fTabs; t++) {
-                fPretty.append("\t");
-            }
-        }
-    }
-
-    // newline is really a request to add a newline, if we are on a fresh line there is no reason
-    // to add another newline
-    void newline() {
-        if (!fFreshline) {
-            fFreshline = true;
-            fPretty.append("\n");
-            this->lineNumbering();
-        }
-    }
-
-    void lineNumbering() {
-        if (fCountlines) {
-            fPretty.appendf("%4d\t", fLinecount++);
-        }
-    }
-
-    bool fCountlines, fFreshline;
-    int fTabs, fLinecount;
-    size_t fIndex, fLength;
-    SkString fInput, fPretty;
-};
-
-SkString PrettyPrintGLSL(const SkString& input, bool countlines) {
-    GLSLPrettyPrint pp;
-    return pp.prettify(input, countlines);
-}
-
-} // end namespace