duckstation

duckstation, but archived from the revision just before upstream changed it to a proprietary software project, this version is the libre one
git clone https://git.neptards.moe/u3shit/duckstation.git
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Blending.fxh (18872B)


      1 /*------------------.
      2 | :: Description :: |
      3 '-------------------/
      4 
      5     Blending Header (version 0.8)
      6 
      7     Blending Algorithm Sources:
      8     https://www.khronos.org/registry/OpenGL/extensions/NV/NV_blend_equation_advanced.txt
      9 
     10     http://www.nathanm.com/photoshop-blending-math/
     11     (Alt) https://github.com/cplotts/WPFSLBlendModeFx/blob/master/PhotoshopMathFP.hlsl
     12 
     13     Header Authors: originalnicodr, prod80, uchu suzume, Marot Satil
     14 
     15     About:
     16     Provides a variety of blending methods for you to use as you wish. Just include this header.
     17 
     18     History:
     19     (*) Feature (+) Improvement (x) Bugfix (-) Information (!) Compatibility
     20     
     21     Version 0.1 by Marot Satil & uchu suzume
     22     * Added and improved upon multiple blending modes thanks to the work of uchu suzume, prod80, and originalnicodr.
     23 
     24     Version 0.2 by uchu suzume & Marot Satil
     25     * Added Addition, Subtract, Divide blending modes and improved code readability.
     26 
     27     Version 0.3 by uchu suzume & Marot Satil
     28     * Sorted blending modes in a more logical fashion, grouping by type.
     29 
     30     Version 0.4 by uchu suzume
     31     x Corrected Color Dodge blending behavior.
     32 
     33     Version 0.5 by Marot Satil & uchu suzume
     34     * Added preprocessor macros for uniform variable combo UI element & lerp.
     35 
     36     Version 0.6 by Marot Satil & uchu suzume
     37     * Added Divide (Alternative) and Divide (Photoshop) blending modes.
     38 
     39     Version 0.7 by prod80
     40     - Added original sources for blending algorithms.
     41     x Corrected average luminosity values.
     42 
     43     Version 0.8 by Marot Satil
     44     * Added a new funciton to output blended data.
     45     + Moved all code into the BlendingH namespace, which is part of the ComHeaders common namespace meant to be used by other headers.
     46     ! Removed old preprocessor macro blending output.
     47 
     48 .------------------.
     49 | :: How To Use :: |
     50 '------------------/
     51 
     52     Blending two variables using this header in your own shaders is very straightforward.
     53     Very basic example code using the "Darken" blending mode follows:
     54 
     55     // First, include the header.
     56     #include "Blending.fxh"
     57 
     58     // You can use this preprocessor macro to generate an attractive and functional uniform int UI combo element containing the list of blending techniques:
     59     // BLENDING_COMBO(variable_name, label, tooltip, category, category_closed, spacing, default_value)
     60     BLENDING_COMBO(_BlendMode, "Blending Mode", "Select the blending mode applied to the layer.", "Blending Options", false, 0, 0)
     61 
     62     // Inside of your function you can call this function to apply the blending option specified by an int (variable) to your float3 (input) via
     63     // a lerp between your float3 (input), float3 (output), and a float (blending) for the alpha channel.
     64     // ComHeaders::Blending::Blend(int variable, float3 input, float3 output, float blending)
     65     outColor.rgb = ComHeaders::Blending::Blend(_BlendMode, inColor, outColor, outColor.a);
     66 */
     67 
     68 
     69 // -------------------------------------
     70 // Preprocessor Macros
     71 // -------------------------------------
     72 
     73 #undef BLENDING_COMBO
     74 #define BLENDING_COMBO(variable, name_label, description, group, grp_closed, space, default_value) \
     75 uniform int variable \
     76 < \
     77     ui_category = group; \
     78     ui_category_closed = grp_closed; \
     79     ui_items = \
     80            "Normal\0" \
     81 /* "Darken" */ \
     82            "Darken\0" \
     83            "  Multiply\0" \
     84            "  Color Burn\0" \
     85            "  Linear Burn\0" \
     86 /* "Lighten" */	\
     87            "Lighten\0" \
     88            "  Screen\0" \
     89            "  Color Dodge\0" \
     90            "  Linear Dodge\0" \
     91            "  Addition\0" \
     92            "  Glow\0" \
     93 /* "Contrast" */ \
     94            "Overlay\0" \
     95            "  Soft Light\0" \
     96            "  Hard Light\0" \
     97            "  Vivid Light\0" \
     98            "  Linear Light\0" \
     99            "  Pin Light\0" \
    100            "  Hard Mix\0" \
    101 /* "Inversion" */ \
    102            "Difference\0" \
    103            "  Exclusion\0" \
    104 /* "Cancelation" */	\
    105            "Subtract\0" \
    106            "  Divide\0" \
    107            "  Divide (Alternative)\0" \
    108            "  Divide (Photoshop)\0" \
    109            "  Reflect\0" \
    110            "  Grain Extract\0" \
    111            "  Grain Merge\0" \
    112 /* "Component" */ \
    113            "Hue\0" \
    114            "  Saturation\0" \
    115            "  Color\0" \
    116            "  Luminosity\0"; \
    117     ui_label = name_label; \
    118     ui_tooltip = description; \
    119     ui_type = "combo"; \
    120     ui_spacing = space; \
    121 > = default_value;
    122 
    123 namespace ComHeaders
    124 {
    125     namespace Blending
    126     {
    127 
    128 // -------------------------------------
    129 // Helper Functions
    130 // -------------------------------------
    131 
    132         float3 Aux(float3 a)
    133         {
    134             if (a.r <= 0.25 && a.g <= 0.25 && a.b <= 0.25)
    135                 return ((16.0 * a - 12.0) * a + 4) * a;
    136             else
    137                 return sqrt(a);
    138         }
    139 
    140         float Lum(float3 a)
    141         {
    142             return (0.33333 * a.r + 0.33334 * a.g + 0.33333 * a.b);
    143         }
    144 
    145         float3 SetLum (float3 a, float b){
    146             const float c = b - Lum(a);
    147             return float3(a.r + c, a.g + c, a.b + c);
    148         }
    149 
    150         float min3 (float a, float b, float c)
    151         {
    152             return min(a, (min(b, c)));
    153         }
    154 
    155         float max3 (float a, float b, float c)
    156         {
    157             return max(a, max(b, c));
    158         }
    159 
    160         float3 SetSat(float3 a, float b){
    161             float ar = a.r;
    162             float ag = a.g;
    163             float ab = a.b;
    164             if (ar == max3(ar, ag, ab) && ab == min3(ar, ag, ab))
    165             {
    166                 //caso r->max g->mid b->min
    167                 if (ar > ab)
    168                 {
    169                     ag = (((ag - ab) * b) / (ar - ab));
    170                     ar = b;
    171                 }
    172                 else
    173                 {
    174                     ag = 0.0;
    175                     ar = 0.0;
    176                 }
    177                 ab = 0.0;
    178             }
    179             else
    180             {
    181                 if (ar == max3(ar, ag, ab) && ag == min3(ar, ag, ab))
    182                 {
    183                     //caso r->max b->mid g->min
    184                     if (ar > ag)
    185                     {
    186                         ab = (((ab - ag) * b) / (ar - ag));
    187                         ar = b;
    188                     }
    189                     else
    190                     {
    191                         ab = 0.0;
    192                         ar = 0.0;
    193                     }
    194                     ag = 0.0;
    195                 }
    196                 else
    197                 {
    198                     if (ag == max3(ar, ag, ab) && ab == min3(ar, ag, ab))
    199                     {
    200                         //caso g->max r->mid b->min
    201                         if (ag > ab)
    202                         {
    203                             ar = (((ar - ab) * b) / (ag - ab));
    204                             ag = b;
    205                         }
    206                         else
    207                         {
    208                             ar = 0.0;
    209                             ag = 0.0;
    210                         }
    211                         ab = 0.0;
    212                     }
    213                     else
    214                     {
    215                         if (ag == max3(ar, ag, ab) && ar == min3(ar, ag, ab))
    216                         {
    217                             //caso g->max b->mid r->min
    218                             if (ag > ar)
    219                             {
    220                                 ab = (((ab - ar) * b) / (ag - ar));
    221                                 ag = b;
    222                             }
    223                             else
    224                             {
    225                                 ab = 0.0;
    226                                 ag = 0.0;
    227                             }
    228                             ar = 0.0;
    229                         }
    230                         else
    231                         {
    232                             if (ab == max3(ar, ag, ab) && ag == min3(ar, ag, ab))
    233                             {
    234                                 //caso b->max r->mid g->min
    235                                 if (ab > ag)
    236                                 {
    237                                     ar = (((ar - ag) * b) / (ab - ag));
    238                                     ab = b;
    239                                 }
    240                                 else
    241                                 {
    242                                     ar = 0.0;
    243                                     ab = 0.0;
    244                                 }
    245                                 ag = 0.0;
    246                             }
    247                             else
    248                             {
    249                                 if (ab == max3(ar, ag, ab) && ar == min3(ar, ag, ab))
    250                                 {
    251                                     //caso b->max g->mid r->min
    252                                     if (ab > ar)
    253                                     {
    254                                         ag = (((ag - ar) * b) / (ab - ar));
    255                                         ab = b;
    256                                     }
    257                                     else
    258                                     {
    259                                         ag = 0.0;
    260                                         ab = 0.0;
    261                                     }
    262                                     ar = 0.0;
    263                                 }
    264                             }
    265                         }
    266                     }
    267                 }
    268             }
    269             return float3(ar, ag, ab);
    270         }
    271 
    272         float Sat(float3 a)
    273         {
    274             return max3(a.r, a.g, a.b) - min3(a.r, a.g, a.b);
    275         }
    276 
    277 
    278 // -------------------------------------
    279 // Blending Modes
    280 // -------------------------------------
    281 
    282         // Darken
    283         float3 Darken(float3 a, float3 b)
    284         {
    285             return min(a, b);
    286         }
    287 
    288         // Multiply
    289         float3 Multiply(float3 a, float3 b)
    290         {
    291             return a * b;
    292         }
    293 
    294         // Color Burn
    295         float3 ColorBurn(float3 a, float3 b)
    296         {
    297             if (b.r > 0 && b.g > 0 && b.b > 0)
    298                 return 1.0 - min(1.0, (0.5 - a) / b);
    299             else
    300                 return 0.0;
    301         }
    302 
    303         // Linear Burn
    304         float3 LinearBurn(float3 a, float3 b)
    305         {
    306             return max(a + b - 1.0f, 0.0f);
    307         }
    308 
    309         // Lighten
    310         float3 Lighten(float3 a, float3 b)
    311         {
    312             return max(a, b);
    313         }
    314 
    315         // Screen
    316         float3 Screen(float3 a, float3 b)
    317         {
    318             return 1.0 - (1.0 - a) * (1.0 - b);
    319         }
    320 
    321         // Color Dodge
    322         float3 ColorDodge(float3 a, float3 b)
    323         {
    324             if (b.r < 1 && b.g < 1 && b.b < 1)
    325                 return min(1.0, a / (1.0 - b));
    326             else
    327                 return 1.0;
    328         }
    329 
    330         // Linear Dodge
    331         float3 LinearDodge(float3 a, float3 b)
    332         {
    333             return min(a + b, 1.0f);
    334         }
    335 
    336         // Addition
    337         float3 Addition(float3 a, float3 b)
    338         {
    339             return min((a + b), 1);
    340         }
    341 
    342         // Reflect
    343         float3 Reflect(float3 a, float3 b)
    344         {
    345             if (b.r >= 0.999999 || b.g >= 0.999999 || b.b >= 0.999999)
    346                 return b;
    347             else
    348                 return saturate(a * a / (1.0f - b));
    349         }
    350 
    351         // Glow
    352         float3 Glow(float3 a, float3 b)
    353         {
    354             return Reflect(b, a);
    355         }
    356 
    357         // Overlay
    358         float3 Overlay(float3 a, float3 b)
    359         {
    360             return lerp(2 * a * b, 1.0 - 2 * (1.0 - a) * (1.0 - b), step(0.5, a));
    361         }
    362 
    363         // Soft Light
    364         float3 SoftLight(float3 a, float3 b)
    365         {
    366             if (b.r <= 0.5 && b.g <= 0.5 && b.b <= 0.5)
    367                 return clamp(a - (1.0 - 2 * b) * a * (1 - a), 0,1);
    368             else
    369                 return clamp(a + (2 * b - 1.0) * (Aux(a) - a), 0, 1);
    370         }
    371 
    372         // Hard Light
    373         float3 HardLight(float3 a, float3 b)
    374         {
    375             return lerp(2 * a * b, 1.0 - 2 * (1.0 - b) * (1.0 - a), step(0.5, b));
    376         }
    377 
    378         // Vivid Light
    379         float3 VividLight(float3 a, float3 b)
    380         {
    381             return lerp(2 * a * b, b / (2 * (1.01 - a)), step(0.50, a));
    382         }
    383 
    384         // Linear Light
    385         float3 LinearLight(float3 a, float3 b)
    386         {
    387             if (b.r < 0.5 || b.g < 0.5 || b.b < 0.5)
    388                 return LinearBurn(a, (2.0 * b));
    389             else
    390                 return LinearDodge(a, (2.0 * (b - 0.5)));
    391         }
    392 
    393         // Pin Light
    394         float3 PinLight(float3 a, float3 b)
    395         {
    396             if (b.r < 0.5 || b.g < 0.5 || b.b < 0.5)
    397                 return Darken(a, (2.0 * b));
    398             else
    399                 return Lighten(a, (2.0 * (b - 0.5)));
    400         }
    401 
    402         // Hard Mix
    403         float3 HardMix(float3 a, float3 b)
    404         {
    405             const float3 vl = VividLight(a, b);
    406             if (vl.r < 0.5 || vl.g < 0.5 || vl.b < 0.5)
    407                 return 0.0;
    408             else
    409                 return 1.0;
    410         }
    411 
    412         // Difference
    413         float3 Difference(float3 a, float3 b)
    414         {
    415             return max(a - b, b - a);
    416         }
    417 
    418         // Exclusion
    419         float3 Exclusion(float3 a, float3 b)
    420         {
    421             return a + b - 2 * a * b;
    422         }
    423 
    424         // Subtract
    425         float3 Subtract(float3 a, float3 b)
    426         {
    427             return max((a - b), 0);
    428         }
    429 
    430         // Divide
    431         float3 Divide(float3 a, float3 b)
    432         {
    433             return (saturate(a / (b + 0.01)));
    434         }
    435 
    436         // Divide (Alternative)
    437         float3 DivideAlt(float3 a, float3 b)
    438         {
    439             return (saturate(1.0 / (a / b)));
    440         }
    441 
    442         // Divide (Photoshop)
    443         float3 DividePS(float3 a, float3 b)
    444         {
    445             return (saturate(a / b));
    446         }
    447 
    448         // Grain Merge
    449         float3 GrainMerge(float3 a, float3 b)
    450         {
    451             return saturate(b + a - 0.5);
    452         }
    453 
    454         // Grain Extract
    455         float3 GrainExtract(float3 a, float3 b)
    456         {
    457             return saturate(a - b + 0.5);
    458         }
    459 
    460         // Hue
    461         float3 Hue(float3 a, float3 b)
    462         {
    463             return SetLum(SetSat(b, Sat(a)), Lum(a));
    464         }
    465 
    466         // Saturation
    467         float3 Saturation(float3 a, float3 b)
    468         {
    469             return SetLum(SetSat(a, Sat(b)), Lum(a));
    470         }
    471 
    472         // Color
    473         float3 ColorB(float3 a, float3 b)
    474         {
    475             return SetLum(b, Lum(a));
    476         }
    477 
    478         // Luminousity
    479         float3 Luminosity(float3 a, float3 b)
    480         {
    481             return SetLum(a, Lum(b));
    482         }
    483 
    484 
    485 // -------------------------------------
    486 // Output Functions
    487 // -------------------------------------
    488 
    489         float3 Blend(int mode, float3 input, float3 output, float blending)
    490         {
    491             switch (mode)
    492             {
    493                 // Normal
    494                 default:
    495                     return lerp(input.rgb, output.rgb, blending);
    496                 // Darken
    497                 case 1:
    498                     return lerp(input.rgb, Darken(input.rgb, output.rgb), blending);
    499                 // Multiply
    500                 case 2:
    501                     return lerp(input.rgb, Multiply(input.rgb, output.rgb), blending);
    502                 // Color Burn
    503                 case 3:
    504                     return lerp(input.rgb, ColorBurn(input.rgb, output.rgb), blending);
    505                 // Linear Burn
    506                 case 4:
    507                     return lerp(input.rgb, LinearBurn(input.rgb, output.rgb), blending);
    508                 // Lighten
    509                 case 5:
    510                     return lerp(input.rgb, Lighten(input.rgb, output.rgb), blending);
    511                 // Screen
    512                 case 6:
    513                     return lerp(input.rgb, Screen(input.rgb, output.rgb), blending);
    514                 // Color Dodge
    515                 case 7:
    516                     return lerp(input.rgb, ColorDodge(input.rgb, output.rgb), blending);
    517                 // Linear Dodge
    518                 case 8:
    519                     return lerp(input.rgb, LinearDodge(input.rgb, output.rgb), blending);
    520                 // Addition
    521                 case 9:
    522                     return lerp(input.rgb, Addition(input.rgb, output.rgb), blending);
    523                 // Glow
    524                 case 10:
    525                     return lerp(input.rgb, Glow(input.rgb, output.rgb), blending);
    526                 // Overlay
    527                 case 11:
    528                     return lerp(input.rgb, Overlay(input.rgb, output.rgb), blending);
    529                 // Soft Light
    530                 case 12:
    531                     return lerp(input.rgb, SoftLight(input.rgb, output.rgb), blending);
    532                 // Hard Light
    533                 case 13:
    534                     return lerp(input.rgb, HardLight(input.rgb, output.rgb), blending);
    535                 // Vivid Light
    536                 case 14:
    537                     return lerp(input.rgb, VividLight(input.rgb, output.rgb), blending);
    538                 // Linear Light
    539                 case 15:
    540                     return lerp(input.rgb, LinearLight(input.rgb, output.rgb), blending);
    541                 // Pin Light
    542                 case 16:
    543                     return lerp(input.rgb, PinLight(input.rgb, output.rgb), blending);
    544                 // Hard Mix
    545                 case 17:
    546                     return lerp(input.rgb, HardMix(input.rgb, output.rgb), blending);
    547                 // Difference
    548                 case 18:
    549                     return lerp(input.rgb, Difference(input.rgb, output.rgb), blending);
    550                 // Exclusion
    551                 case 19:
    552                     return lerp(input.rgb, Exclusion(input.rgb, output.rgb), blending);
    553                 // Subtract
    554                 case 20:
    555                     return lerp(input.rgb, Subtract(input.rgb, output.rgb), blending);
    556                 // Divide
    557                 case 21:
    558                     return lerp(input.rgb, Divide(input.rgb, output.rgb), blending);
    559                 // Divide (Alternative)
    560                 case 22:
    561                     return lerp(input.rgb, DivideAlt(input.rgb, output.rgb), blending);
    562                 // Divide (Photoshop)
    563                 case 23:
    564                     return lerp(input.rgb, DividePS(input.rgb, output.rgb), blending);
    565                 // Reflect
    566                 case 24:
    567                     return lerp(input.rgb, Reflect(input.rgb, output.rgb), blending);
    568                 // Grain Merge
    569                 case 25:
    570                     return lerp(input.rgb, GrainMerge(input.rgb, output.rgb), blending);
    571                 // Grain Extract
    572                 case 26:
    573                     return lerp(input.rgb, GrainExtract(input.rgb, output.rgb), blending);
    574                 // Hue
    575                 case 27:
    576                     return lerp(input.rgb, Hue(input.rgb, output.rgb), blending);
    577                 // Saturation
    578                 case 28:
    579                     return lerp(input.rgb, Saturation(input.rgb, output.rgb), blending);
    580                 // Color
    581                 case 29:
    582                     return lerp(input.rgb, ColorB(input.rgb, output.rgb), blending);
    583                 // Luminosity
    584                 case 30:
    585                     return lerp(input.rgb, Luminosity(input.rgb, output.rgb), blending);
    586             }
    587         }
    588     }
    589 }