urho3d/Engine/UI/Text.cpp

//
// Urho3D Engine
// Copyright (c) 2008-2011 Lasse Öörni
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//

#include "Precompiled.h"
#include "Font.h"
#include "Log.h"
#include "Profiler.h"
#include "ResourceCache.h"
#include "Text.h"
#include "Texture.h"

#include "DebugNew.h"

Text::Text(const std::string& text, const std::string& name) :
    UIElement(name),
    mFontSize(DEFAULT_FONT_SIZE),
    mMaxWidth(0),
    mText(text),
    mTextAlignment(HA_LEFT),
    mTextSpacing(1.0f)
{
}

Text::~Text()
{
}

void Text::setStyle(const XMLElement& element, ResourceCache* cache)
{
    if (!cache)
        EXCEPTION("Null resource cache for UI element");
    
    UIElement::setStyle(element, cache);
    
    if (element.hasChildElement("font"))
    {
        XMLElement fontElem = element.getChildElement("font");
        setFont(cache->getResource<Font>(fontElem.getString("name")), fontElem.getInt("size"));
    }
    if (element.hasChildElement("maxwidth"))
        setMaxWidth(element.getChildElement("maxwidth").getInt("value"));
    if (element.hasChildElement("text"))
        setText(element.getChildElement("text").getString("value"));
    if (element.hasChildElement("textspacing"))
        setTextSpacing(element.getChildElement("textspacing").getFloat("value"));
    if (element.hasChildElement("textalignment"))
    {
        std::string horiz = element.getChildElement("textalignment").getStringLower("value");
        if (horiz == "left")
            setTextAlignment(HA_LEFT);
        if (horiz == "center")
            setTextAlignment(HA_CENTER);
        if (horiz == "right")
            setTextAlignment(HA_RIGHT);
    }
}

bool Text::setFont(Font* font, int size)
{
    if (!font)
    {
        LOGERROR("Null font for Text");
        return false;
    }
    
    mFont = font;
    mFontSize = max(size, 1);
    
    // Catch exception if executed from script
    try
    {
        calculateTextSize();
    }
    catch (Exception& e)
    {
        mFont = 0;
        SAFE_RETHROW_RET(e, false);
    }
    
    return true;
}

void Text::setMaxWidth(int maxWidth)
{
    mMaxWidth = max(maxWidth, 0);
    calculateTextSize();
}

void Text::setText(const std::string& text)
{
    mText = text;
    calculateTextSize();
}

void Text::setTextAlignment(HorizontalAlignment align)
{
    mTextAlignment = align;
}

void Text::setTextSpacing(float spacing)
{
    mTextSpacing = max(spacing, 0.5f);
}

void Text::getBatches(std::vector<UIBatch>& batches, std::vector<UIQuad>& quads, const IntRect& currentScissor)
{
    if (!mFont)
    {
        mHovering = false;
        return;
    }
    
    const FontFace* face = mFont->getFace(mFontSize);
    
    UIBatch batch;
    batch.begin(&quads);
    batch.mBlendMode = BLEND_ALPHA;
    batch.mScissor = currentScissor;
    batch.mTexture = face->mTexture;
    
    unsigned rowIndex = 0;
    int x = getRowStartPosition(rowIndex);
    int y = 0;
    int rowHeight = (int)(mTextSpacing * face->mRowHeight);
    
    for (unsigned i = 0; i < mPrintText.length(); ++i)
    {
        unsigned char c = (unsigned char)mPrintText[i];
        
        if (c != '\n')
        {
            const FontGlyph& glyph = face->mGlyphs[face->mGlyphIndex[c]];
            if (c != ' ')
                batch.addQuad(*this, x + glyph.mOffsetX, y + glyph.mOffsetY, glyph.mWidth, glyph.mHeight, glyph.mX, glyph.mY);
            x += glyph.mAdvanceX;
        }
        else
        {
            rowIndex++;
            x = getRowStartPosition(rowIndex);
            y += rowHeight;
        }
    }
    
    UIBatch::addOrMerge(batch, batches);
    
    // Reset hovering for next frame
    mHovering = false;
}

int Text::getRowHeight() const
{
    if (mFont)
        return mFont->getFace(mFontSize)->mRowHeight;
    else
        return 0;
}

void Text::calculateTextSize()
{
    int width = 0;
    int height = 0;
    
    mRowWidths.clear();
    
    if (mFont)
    {
        const FontFace* face = mFont->getFace(mFontSize);
        int rowWidth = 0;
        int rowHeight = (int)(mTextSpacing * face->mRowHeight);
        
        // First see if the text must be split up
        if (!mMaxWidth)
            mPrintText = mText;
        else
        {
            unsigned nextBreak = 0;
            unsigned lineStart = 0;
            for (unsigned i = 0; i < mText.length(); ++i)
            {
                unsigned j;
                if (mText[i] != '\n')
                {
                    bool ok = true;
                    
                    if (nextBreak <= i)
                    {
                        int futureRowWidth = rowWidth;
                        for (j = i; j < mText.length(); ++j)
                        {
                            if ((mText[j] == ' ') || (mText[j] == '\n'))
                            {
                                nextBreak = j;
                                break;
                            }
                            futureRowWidth += face->mGlyphs[face->mGlyphIndex[mText[j]]].mAdvanceX;
                            if ((mText[j] == '-') && (futureRowWidth <= mMaxWidth))
                            {
                                nextBreak = j + 1;
                                break;
                            }
                            if (futureRowWidth > mMaxWidth)
                            {
                                ok = false;
                                break;
                            }
                        }
                    }
                    
                    if (!ok)
                    {
                        // If did not find any breaks on the line, copy until j, or at least 1 char, to prevent infinite loop
                        if (nextBreak == lineStart)
                        {
                            int copyLength = max(j - i, 1);
                            mPrintText.append(mText.substr(i, copyLength));
                            i += copyLength;
                        }
                        mPrintText += '\n';
                        rowWidth = 0;
                        nextBreak = lineStart = i;
                    }
                    
                    if (i < mText.length())
                    {
                        // When copying a space, we may be over row width
                        rowWidth += face->mGlyphs[face->mGlyphIndex[mText[i]]].mAdvanceX;
                        if (rowWidth <= mMaxWidth)
                            mPrintText += mText[i];
                    }
                }
                else
                {
                    mPrintText += '\n';
                    rowWidth = 0;
                    nextBreak = lineStart = i;
                }
            }
        }
        
        rowWidth = 0;
        
        for (unsigned i = 0; i < mPrintText.length(); ++i)
        {
            unsigned char c = (unsigned char)mPrintText[i];
            
            if (c != '\n')
            {
                const FontGlyph& glyph = face->mGlyphs[face->mGlyphIndex[c]];
                rowWidth += glyph.mAdvanceX;
            }
            else
            {
                width = max(width, rowWidth);
                height += rowHeight;
                mRowWidths.push_back(rowWidth);
                rowWidth = 0;
            }
        }
        
        if (rowWidth)
        {
            width = max(width, rowWidth);
            height += rowHeight;
            mRowWidths.push_back(rowWidth);
        }
    }
    
    setSize(width, height);
}

int Text::getRowStartPosition(unsigned rowIndex) const
{
    int rowWidth = 0;
    
    if (rowIndex < mRowWidths.size())
        rowWidth = mRowWidths[rowIndex];
    
    switch (mTextAlignment)
    {
    default:
        return 0;
    case HA_CENTER:
        return (getSize().mX - rowWidth) / 2;
    case HA_RIGHT:
        return getSize().mX - rowWidth;
    }
}