diff options
Diffstat (limited to 'src/fl_plastic.cxx')
| -rw-r--r-- | src/fl_plastic.cxx | 90 |
1 files changed, 87 insertions, 3 deletions
diff --git a/src/fl_plastic.cxx b/src/fl_plastic.cxx index 0830f0451..5030ac389 100644 --- a/src/fl_plastic.cxx +++ b/src/fl_plastic.cxx @@ -18,18 +18,102 @@ // https://www.fltk.org/bugs.php // +/** + \file src/fl_plastic.cxx + \brief Implementation of the \c 'plastic' scheme. +*/ + // Box drawing code for an obscure box type. // These box types are in separate files so they are not linked // in if not used. #include <FL/Fl.H> +#include <FL/Fl_Scheme.H> #include <FL/fl_draw.H> -#include "flstring.h" -extern const uchar *fl_gray_ramp(); +#include <cassert> + +// Globals + +extern const uchar *fl_gray_ramp(); // in src/fl_boxtype.cxx + +// Module globals (static) + +static float plastic_average = -1.00f; // plastic color average: not yet set +static int av_min = 10; // min. supported average +static int av_def = 75; // default average (up to FLTK 1.4) +static int av_max = 100; // max. supported average + + +// clamp and set color average value + +static void set_color_average(int av) { + if (av < av_min) + plastic_average = av_min / 100.f; + else if (av > av_max) + plastic_average = av_max / 100.f; + else + plastic_average = av / 100.f; +} + +/** + Set the color average value of the 'plastic' scheme in percent. + + Legal values are in the range [ 10 ... 100 ], other values are clamped. The + default value is 75 which is backwards compatible with FLTK 1.4 and earlier. + + Higher values make the colors in boxes etc. appear "more gray" whereas lower + values make colors appear more like the original color. The recommended value + is about 40 to 60 but this is left to the user. + + If this method is not called then the environment variable \c FLTK_PLASTIC_AVERAGE + can be used to set the color average. The environment variable must be a pure + numeric (integer) value in the given range, otherwise the behavior is undefined. + + However, calling \b this method takes precedence over the environment variable. + This method can be called at any time (e.g. to view dynamic changes). This will + permanently change the appearance for all later box / background drawings. + + For details see GitHub Issue 464: "RFE: plastic scheme with faithful colors". + + \note Program developers are supposed to use this method to apply "better" + values than the default (1.4) look and feel. End users are supposed to use + the environment variable for programs that \b don't use + Fl_Scheme::plastic_color_average(). + + Include the following header: + \code + #include <FL/Fl_Scheme.H> + \endcode + + \param[in] av color average value in the documented range. + + \since 1.5.0 +*/ +void Fl_Scheme::plastic_color_average(int av) { + set_color_average(av); +} + +// Get 'plastic' color average from environment variable 'FLTK_PLASTIC_AVERAGE' +// unless it has already been set. +// See GitHub Issue # 464: "RFE: plastic scheme with faithful colors" + +static float plastic_color_average() { + if (plastic_average < 0.0f) { // only once + char *envvar = fl_getenv("FLTK_PLASTIC_AVERAGE"); + if (envvar) { // convert and store env. var. + int temp = atoi(envvar); // may be 0, but will be clamped + set_color_average(temp); // clamp and set value + } else { + plastic_average = av_def / 100.0f; // set default value + } + } + assert(plastic_average >= 0); + return plastic_average; +} inline Fl_Color shade_color(uchar gc, Fl_Color bc) { - return fl_color_average((Fl_Color)gc, bc, 0.75f); + return fl_color_average((Fl_Color)gc, bc, plastic_color_average()); } static void frame_rect(int x, int y, int w, int h, const char *c, Fl_Color bc) { |