/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 Robert Osfield
*
* This library is open source and may be redistributed and/or modified under
* the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
* (at your option) any later version. The full license is in LICENSE file
* included with this distribution, and on the openscenegraph.org website.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* OpenSceneGraph Public License for more details.
*/
#ifndef OSGTEXT_TEXT
#define OSGTEXT_TEXT 1
#include <osg/Drawable>
#include <osg/Quat>
#include <osgText/TextBase>
#include <osgText/Font>
namespace osgText {
class OSGTEXT_EXPORT Text : public osgText::TextBase
{
public:
Text();
Text(const Text& text,const osg::CopyOp& copyop=osg::CopyOp::SHALLOW_COPY);
virtual osg::Object* cloneType() const { return new Text(); }
virtual osg::Object* clone(const osg::CopyOp& copyop) const { return new Text(*this,copyop); }
virtual bool isSameKindAs(const osg::Object* obj) const { return dynamic_cast<const Text*>(obj)!=NULL; }
virtual const char* className() const { return "Text"; }
virtual const char* libraryName() const { return "osgText"; }
/** Set the ShaderTechnique hint to specify what fatures in the text shaders to enable.*/
void setShaderTechnique(ShaderTechnique technique);
/** Get the ShaderTechnique hint.*/
ShaderTechnique getShaderTechnique() { return _shaderTechnique; }
/**
* Turns off writing to the depth buffer when rendering text. This only affects text
* with no backdrop or text using the DELAYED_DEPTH_WRITES implementation, since
* the other backdrop implementations are really only useful for backwards
* compatibility and are not worth updating to utilize this flag.
*/
void setEnableDepthWrites(bool enable) { _enableDepthWrites = enable; }
bool getEnableDepthWrites() const { return _enableDepthWrites; }
enum BackdropType
{
DROP_SHADOW_BOTTOM_RIGHT = 0, // usually the type of shadow you see
DROP_SHADOW_CENTER_RIGHT,
DROP_SHADOW_TOP_RIGHT,
DROP_SHADOW_BOTTOM_CENTER,
DROP_SHADOW_TOP_CENTER,
DROP_SHADOW_BOTTOM_LEFT,
DROP_SHADOW_CENTER_LEFT,
DROP_SHADOW_TOP_LEFT,
OUTLINE,
NONE
};
/**
* BackdropType gives you a background shadow text behind your regular
* text. This helps give text extra contrast which can be useful when
* placing text against noisy backgrounds.
* The color of the background shadow text is specified by setBackdropColor().
* DROP_SHADOW_BOTTOM_RIGHT will draw backdrop text to the right and down of
* the normal text. Other DROP_SHADOW_* modes do the same for their respective directions.
* OUTLINE will draw backdrop text so that it appears the text has an outline
* or border around the normal text. This mode is particularly useful against
* really noisy backgrounds that may put text on top of things that have
* all types of colors which you don't have control over.
* Some real world examples of this general technique in use that I know of
* are Google Earth, Sid Meier's Pirates (2004 Remake), and Star Control 2 (PC 1993).
* The default is NONE.
*/
void setBackdropType(BackdropType type);
BackdropType getBackdropType() const { return _backdropType; }
/**
* Sets the amount text is offset to create the backdrop/shadow effect.
* Set the value too high and for example, in OUTLINE mode you will get a "Brady Bunch"
* effect where you see duplicates of the text in a 3x3 grid.
* Set the value too small and you won't see anything.
* The values represent percentages. 1.0 means 100% so a value of 1.0
* in DROW_SHADOW_LEFT_CENTER mode would cause each glyph to be echoed
* next to it self. So the letter 'e' might look like 'ee'.
* Good values tend to be in the 0.03 to 0.10 range (but will be subject
* to your specific font and display characteristics).
* Note that the text bounding boxes are updated to include backdrop offsets.
* However, other metric information such as getCharacterHeight() are unaffected
* by this. This means that individual glyph spacing (kerning?) are unchanged
* even when this mode is used.
* The default is 0.07 (7% offset).
*/
void setBackdropOffset(float offset = 0.07f);
/**
* This overloaded version lets you specify the offset for the horizontal
* and vertical components separately.
*/
void setBackdropOffset(float horizontal, float vertical);
float getBackdropHorizontalOffset() const { return _backdropHorizontalOffset; }
float getBackdropVerticalOffset() const { return _backdropVerticalOffset; }
/**
* This specifies the color of the backdrop text.
* The default is black.
*/
void setBackdropColor(const osg::Vec4& color);
const osg::Vec4& getBackdropColor() const { return _backdropColor; }
enum ColorGradientMode
{
SOLID = 0, // a.k.a. ColorGradients off
PER_CHARACTER,
OVERALL
};
/**
* This sets different types of text coloring modes.
* When the coloring mode is not set to SOLID, the
* colors specified in setColorGradientCorners() determine
* the colors for the text.
* When the gradient mode is OVERALL, the coloring scheme
* attempts to approximate the effect as if the entire text box/region
* were a single polygon and you had applied colors to each of the four
* corners with GL_SMOOTH enabled. In this mode, OpenGL interpolates
* the colors across the polygon, and this is what OVERALL tries to
* emulate. This can be used to give nice embellishments on things
* like logos and names.
* PER_CHARACTER is similar to OVERALL except that it applies the
* color interpolation to the four corners of each character instead
* of across the overall text box.
* The default is SOLID (a.k.a. off).
*/
void setColorGradientMode(ColorGradientMode mode);
ColorGradientMode getColorGradientMode() const { return _colorGradientMode; }
/**
* Used only for gradient mode, let's you specify the colors of the 4 corners.
* If ColorGradients are off, these values are ignored (and the value from setColor()
* is the only one that is relevant.
*/
void setColorGradientCorners(const osg::Vec4& topLeft, const osg::Vec4& bottomLeft, const osg::Vec4& bottomRight, const osg::Vec4& topRight);
const osg::Vec4& getColorGradientTopLeft() const { return _colorGradientTopLeft; }
const osg::Vec4& getColorGradientBottomLeft() const { return _colorGradientBottomLeft; }
const osg::Vec4& getColorGradientBottomRight() const { return _colorGradientBottomRight; }
const osg::Vec4& getColorGradientTopRight() const { return _colorGradientTopRight; }
/** Draw the text.*/
virtual void drawImplementation(osg::RenderInfo& renderInfo) const;
/** return false, osgText::Text does not support accept(AttributeFunctor&).*/
virtual bool supports(const osg::Drawable::AttributeFunctor&) const { return false; }
/** return true, osgText::Text does support accept(ConstAttributeFunctor&).*/
virtual bool supports(const osg::Drawable::ConstAttributeFunctor&) const { return true; }
/** accept an ConstAttributeFunctor and call its methods to tell it about the internal attributes that this Drawable has.*/
virtual void accept(osg::Drawable::ConstAttributeFunctor& af) const;
/** return true, osgText::Text does support accept(PrimitiveFunctor&) .*/
virtual bool supports(const osg::PrimitiveFunctor&) const { return true; }
/** accept a PrimtiveFunctor and call its methods to tell it about the internal primitives that this Drawable has.*/
virtual void accept(osg::PrimitiveFunctor& pf) const;
/** Get the coordinates of the character corners in local coordinates. Use Text::getMatrix() or Text::computeMatrix(..) to get the transform into model coordinates (see TextBase header.) */
bool getCharacterCorners(unsigned int index, osg::Vec3& bottomLeft, osg::Vec3& bottomRight, osg::Vec3& topLeft, osg::Vec3& topRight) const;
/** Resize any per context GLObject buffers to specified size. */
virtual void resizeGLObjectBuffers(unsigned int maxSize);
/** If State is non-zero, this function releases OpenGL objects for
* the specified graphics context. Otherwise, releases OpenGL objexts
* for all graphics contexts. */
virtual void releaseGLObjects(osg::State* state=0) const;
public:
/** deprecated, value ignored.*/
enum BackdropImplementation
{
POLYGON_OFFSET = 0,
NO_DEPTH_BUFFER,
DEPTH_RANGE,
STENCIL_BUFFER,
DELAYED_DEPTH_WRITES
};
/** deprecated, value ignored.*/
void setBackdropImplementation(BackdropImplementation) {}
/** deprecated, value should be ignored.*/
BackdropImplementation getBackdropImplementation() const { return DELAYED_DEPTH_WRITES; }
// internal structures, variable and methods used for rendering of characters.
struct OSGTEXT_EXPORT GlyphQuads
{
typedef std::vector<Glyph*> Glyphs;
Glyphs _glyphs;
osg::ref_ptr<osg::DrawElements> _primitives;
GlyphQuads();
GlyphQuads(const GlyphQuads& gq);
void setupPrimitives(Text::BackdropType backdropType);
Glyphs& getGlyphs() { return _glyphs; }
const Glyphs& getGlyphs() const { return _glyphs; }
/** Resize any per context GLObject buffers to specified size. */
void resizeGLObjectBuffers(unsigned int maxSize);
/** If State is non-zero, this function releases OpenGL objects for
* the specified graphics context. Otherwise, releases OpenGL objexts
* for all graphics contexts. */
void releaseGLObjects(osg::State* state=0) const;
private:
GlyphQuads& operator = (const GlyphQuads&) { return *this; }
};
typedef std::map<osg::ref_ptr<GlyphTexture>,GlyphQuads> TextureGlyphQuadMap;
/** Direct Access to GlyphQuads */
const GlyphQuads* getGlyphQuads(GlyphTexture* texture) const
{
TextureGlyphQuadMap::const_iterator itGlyphQuad = _textureGlyphQuadMap.find(texture);
if (itGlyphQuad == _textureGlyphQuadMap.end()) return NULL;
return &itGlyphQuad->second;
}
const TextureGlyphQuadMap& getTextureGlyphQuadMap() const
{
return _textureGlyphQuadMap;
}
void addGlyphQuad(Glyph* glyph, const osg::Vec2& minc, const osg::Vec2& maxc, const osg::Vec2& mintc, const osg::Vec2& maxtc);
protected:
virtual ~Text();
virtual osg::StateSet* createStateSet();
Font* getActiveFont();
String::iterator computeLastCharacterOnLine(osg::Vec2& cursor, String::iterator first,String::iterator last);
// members which have public access.
// iternal map used for rendering. Set up by the computeGlyphRepresentation() method.
TextureGlyphQuadMap _textureGlyphQuadMap;
void computeGlyphRepresentation();
// internal caches of the positioning of the text.
bool computeAverageGlyphWidthAndHeight(float& avg_width, float& avg_height) const;
virtual void computePositionsImplementation();
void computeColorGradients();
void computeColorGradientsOverall();
void computeColorGradientsPerCharacter();
void drawImplementation(osg::State& state, const osg::Vec4& colorMultiplier) const;
void drawImplementationSinglePass(osg::State& state, const osg::Vec4& colorMultiplier) const;
ShaderTechnique _shaderTechnique;
bool _enableDepthWrites;
BackdropType _backdropType;
float _backdropHorizontalOffset;
float _backdropVerticalOffset;
osg::Vec4 _backdropColor;
ColorGradientMode _colorGradientMode;
osg::Vec4 _colorGradientTopLeft;
osg::Vec4 _colorGradientBottomLeft;
osg::Vec4 _colorGradientBottomRight;
osg::Vec4 _colorGradientTopRight;
// Helper function for color interpolation
float bilinearInterpolate(float x1, float x2, float y1, float y2, float x, float y, float q11, float q12, float q21, float q22) const;
};
}
#endif