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diff --git a/documentation/Fl_Image.html b/documentation/Fl_Image.html new file mode 100644 index 000000000..1287a6113 --- /dev/null +++ b/documentation/Fl_Image.html @@ -0,0 +1,142 @@ +<head><title>Fl_Image</title></head><body bgcolor=white> + +<h1>class Fl_Image</h1> + +This class holds an image, normally used to label a widget. The +subclasses define how the data is interpreted, and usually store +server-side cached versions of the image. All the current types +define pixel arrays, but other types of images, such as vector +graphics, can be defined. + +<h2>Methods</h2> + +<h4>ulong id, mask;<br> +void _draw(int X, int Y, int W, int H, int cx, int cy);</h4> + +Subclasses may use these <i>protected</i> members of the base class to +draw a cached pixel array. They must first set <tt>id</tt> and +<tt>mask</tt> to the color and transparency offscreen windows, using +system-specific code. Then they can call <tt>_draw()</tt> to draw +them. + +<h4>int w,h</h4> + +These members hold the width and height of the image. They are not +correct until <tt>measure()</tt> is called. These are public instance +variables for back comptability, but you should never set them. + +<h4>virtual void Fl_Image::measure(int W, int H);</h4> + +Measure how big the image will be if it is drawn inside a W,H +rectangle and put the result into w,h. For most image types this does +nothing and w,h are set by the constructor. This may be used to +initialize the scaling for variable-sized images. + +<h4>virtual void Fl_Image::draw(int x,int y,int w,int h, int cx,int +cy);</h4> + +Draw the image so the point <i>cx,cy</i> of the image is at +<i>x,y</i>. The image may be scaled or clipped to fit in the <i>w,h</i> +rectangle, but this is not necessary (although obeying the current +fl_clip value is!). + +<h4>void Fl_Image::draw(int x,int y,int w,int h, Fl_Flags align);</h4> + +This <i>non-virtual</i> function uses <tt>measure()</tt> and the +<i>align</i> flags to figure out <i>cx,cy</i> and call the normal draw +function. This allows you to center or align any edge of the image +with a bounding box. + +<h4>virtual Fl_Image::~Fl_Image();</h4> + +The destructor throws away any server-cached information, but in most +cases does not destroy the local data passed to a constructor. + +<H2><A name=Fl_Bitmap>class Fl_Bitmap : public Fl_Image</A></H2> + This object encapsulates the width, height, and bits of an X bitmap +(XBM), and allows you to make an <TT>Fl_Widget</TT> use a bitmap as a +label, or to just draw the bitmap directly. + +<H4>Fl_Bitmap(const char *bits, int W, int H) +<BR> Fl_Bitmap(const uchar *bits, int W, int H)</H4> +Construct using an X bitmap. The bits pointer is simply copied to the +object, so it must point at persistent storage. The two constructors +are provided because various X implementations disagree about the type +of bitmap data. To use an XBM file use: +<UL> +<PRE> +#include "foo.xbm" +... +Fl_Bitmap bitmap = new Fl_Bitmap(foo_bits, foo_width, foo_height); +</PRE> +</UL> +<H4>~Fl_Bitmap()</H4> + The destructor will destroy any X pixmap created. It does not do +anything to the bits data. +<H4>void draw(int x, int y, int w, int h, int ox = 0, int oy = 0)</H4> +1 bits are drawn with the current color, 0 bits +are unchanged. +The image is clipped to the destination rectangle: the area +<TT>ox,oy,w,h</TT> is copied to <TT>x,y,w,h</TT>. +<H4>void draw(int x, int y)</H4> +Draws the bitmap with the upper-left corner at <TT>x,y</TT>. This is +the same as doing <TT>draw(x,y,this->w,this->h,0,0)</TT>. + +<H2><A name=Fl_Pixmap>class Fl_Pixmap : public Fl_Image</A></H2> + +This object encapsulates the data from an XPM image, and allows you to +make an <TT>Fl_Widget</TT> use a pixmap as a label, or to just draw +the pixmap directly. + +<H4>Fl_Pixmap(char *const* data)</H4> + Construct using XPM data. The data pointer is simply copied to the +object, so it must point at persistent storage. To use an XPM file do: +<UL> +<PRE> +#include <fltk/Fl_Pixmap.h> +#include "foo.xpm" +... +Fl_Pixmap pixmap = new Fl_Pixmap(foo); +</PRE> +</UL> +<H4>~Fl_Pixmap()</H4> + The destructor will destroy any X pixmap created. It does not do +anything to the data. + +<H4>void draw(int x, int y, int w, int h, int ox = 0, int oy = 0)</H4> +The image is clipped to the destination rectangle: the area +<TT>ox,oy,w,h</TT> is copied to <TT>x,y,w,h</TT>. The current +implementation converts the pixmap to 24-bit RGB data and uses <A +href=#fl_draw_image><TT>fl_draw_image()</TT></A> to draw it. Thus you +will get dithered colors on an 8 bit screen. </P> + +<H4>void draw(int x, int y)</H4> + Draws the image with the upper-left corner at <TT>x,y</TT>. This is +the same as doing <TT>draw(x,y,this->w,this->h,0,0)</TT>. + +<H2><A name=Fl_RGB_Image>class Fl_RGB_Image</A></H2> + +This object encapsulates a full-color RGB image, and allows you to +make an <TT>Fl_Widget</TT> use an image as a label, or to just draw the +image directly. + +<H4>Fl_RGB_Image(const uchar *data, int W, int H, int D = 3, int LD = 0)</H4> + Construct using a pointer to RGB data. <TT>W</TT> and <TT>H</TT> are +the size of the image in pixels. <TT>D</TT> is the delta between pixels +(it may be more than 3 to skip alpha or other data, or negative to flip +the image left/right). <TT>LD</TT> is the delta between lines (it may +be more than <TT>D * W</TT> to crop images, or negative to flip the +image vertically). The data pointer is simply copied to the object, so +it must point at persistent storage. +<H4>~Fl_RGB_Image()</H4> + The destructor will destroy any X pixmap created. It does not do +anything to the data. +<H4>void draw(int x, int y, int w, int h, int ox = 0, int oy = 0)</H4> +The image is clipped to the destination rectangle: the area +<TT>ox,oy,w,h</TT> is copied to <TT>x,y,w,h</TT>. +<H4>void draw(int x, int y)</H4> + Draws the image with the upper-left corner at <TT>x,y</TT>. This is +the same as doing <TT>draw(x,y,this->w,this->h,0,0)</TT>. + +</body></html> + |