Implement texture lookup table GLSL shader, ported from wrath-darkplaces

diff --git a/gl_rmain.c b/gl_rmain.c
index 22e28b7533fff6baefee5479fa58db2cd0d1c646..8f344505746e26a00001fe27d4ff11e6b9abfa18 100644 (file)
--- a/gl_rmain.c
+++ b/gl_rmain.c
@@ -182,6 +182,7 @@ cvar_t r_glsl_offsetmapping_scale = {CVAR_CLIENT | CVAR_SAVE, "r_glsl_offsetmapp
 cvar_t r_glsl_offsetmapping_lod = {CVAR_CLIENT | CVAR_SAVE, "r_glsl_offsetmapping_lod", "0", "apply distance-based level-of-detail correction to number of offsetmappig steps, effectively making it render faster on large open-area maps"};
 cvar_t r_glsl_offsetmapping_lod_distance = {CVAR_CLIENT | CVAR_SAVE, "r_glsl_offsetmapping_lod_distance", "32", "first LOD level distance, second level (-50% steps) is 2x of this, third (33%) - 3x etc."};
 cvar_t r_glsl_postprocess = {CVAR_CLIENT | CVAR_SAVE, "r_glsl_postprocess", "0", "use a GLSL postprocessing shader"};
+cvar_t r_glsl_postprocess_color_lut = {CVAR_CLIENT | CVAR_SAVE, "r_glsl_postprocess_color_lut", "", "color lookup table for post, empty string for default"};
 cvar_t r_glsl_postprocess_uservec1 = {CVAR_CLIENT | CVAR_SAVE, "r_glsl_postprocess_uservec1", "0 0 0 0", "a 4-component vector to pass as uservec1 to the postprocessing shader (only useful if default.glsl has been customized)"};
 cvar_t r_glsl_postprocess_uservec2 = {CVAR_CLIENT | CVAR_SAVE, "r_glsl_postprocess_uservec2", "0 0 0 0", "a 4-component vector to pass as uservec2 to the postprocessing shader (only useful if default.glsl has been customized)"};
 cvar_t r_glsl_postprocess_uservec3 = {CVAR_CLIENT | CVAR_SAVE, "r_glsl_postprocess_uservec3", "0 0 0 0", "a 4-component vector to pass as uservec3 to the postprocessing shader (only useful if default.glsl has been customized)"};
@@ -276,6 +277,9 @@ rtexture_t *r_texture_normalizationcube;
 rtexture_t *r_texture_fogattenuation;
 rtexture_t *r_texture_fogheighttexture;
 rtexture_t *r_texture_gammaramps;
+rtexture_t *r_texture_lut;
+rtexture_t *r_texture_lut_default;
+cachepic_t *r_texture_lut_pic;
 unsigned int r_texture_gammaramps_serial;
 //rtexture_t *r_texture_fogintensity;
 rtexture_t *r_texture_reflectcube;
@@ -611,6 +615,32 @@ static void R_BuildFogHeightTexture(void)
        r_texture_fogheighttexture = R_LoadTexture2D(r_main_texturepool, "fogheighttable", size, size, r_refdef.fog_height_table2d, TEXTYPE_BGRA, TEXF_ALPHA | TEXF_CLAMP, -1, NULL);
 }
 
+#define LUT_SLICE_SIZE 64
+#define LUT_FACTOR (256 / LUT_SLICE_SIZE)
+#define LUT_SLICES_X 8
+#define LUT_SLICES_Y 8
+#define LUT_WIDTH (LUT_SLICE_SIZE * LUT_SLICES_X)
+#define LUT_HEIGHT (LUT_SLICE_SIZE * LUT_SLICES_Y)
+
+static void R_BuildDefaultLUT(void)
+{
+       unsigned char *p, *data;
+       int x, y;
+       data = (unsigned char *)Mem_Alloc(r_main_mempool, LUT_WIDTH * LUT_HEIGHT * 4);
+       p = data;
+       for (y = 0; y < LUT_HEIGHT; ++y)
+               for (x = 0; x < LUT_WIDTH; ++x)
+               {
+                       p[3] = 255;
+                       p[2] = (x % LUT_SLICE_SIZE) * LUT_FACTOR;
+                       p[1] = (y % LUT_SLICE_SIZE) * LUT_FACTOR;
+                       p[0] = ((y / LUT_SLICE_SIZE) * LUT_SLICES_X + x / LUT_SLICE_SIZE) * LUT_FACTOR;
+                       p += 4;
+               }
+       r_texture_lut_default = R_LoadTexture2D(r_main_texturepool, "lutdefault", LUT_WIDTH, LUT_HEIGHT, data, TEXTYPE_BGRA, TEXF_FORCELINEAR | TEXF_CLAMP | TEXF_PERSISTENT, -1, NULL);
+       r_texture_lut = r_texture_lut_default;
+}
+
 //=======================================================================================================================================================
 
 static const char *builtinshaderstrings[] =
@@ -746,6 +776,7 @@ typedef struct r_glsl_permutation_s
        int tex_Texture_ReflectMask;
        int tex_Texture_ReflectCube;
        int tex_Texture_BounceGrid;
+       int tex_Texture_LUT;
        /// locations of detected uniforms in program object, or -1 if not found
        int loc_Texture_First;
        int loc_Texture_Second;
@@ -777,6 +808,7 @@ typedef struct r_glsl_permutation_s
        int loc_Texture_ReflectMask;
        int loc_Texture_ReflectCube;
        int loc_Texture_BounceGrid;
+       int loc_Texture_LUT;
        int loc_Alpha;
        int loc_BloomBlur_Parameters;
        int loc_ClientTime;
@@ -1212,6 +1244,7 @@ static void R_GLSL_CompilePermutation(r_glsl_permutation_t *p, unsigned int mode
                p->loc_Texture_ReflectMask        = qglGetUniformLocation(p->program, "Texture_ReflectMask");
                p->loc_Texture_ReflectCube        = qglGetUniformLocation(p->program, "Texture_ReflectCube");
                p->loc_Texture_BounceGrid         = qglGetUniformLocation(p->program, "Texture_BounceGrid");
+               p->loc_Texture_LUT                = qglGetUniformLocation(p->program, "Texture_LUT");
                p->loc_Alpha                      = qglGetUniformLocation(p->program, "Alpha");
                p->loc_BloomBlur_Parameters       = qglGetUniformLocation(p->program, "BloomBlur_Parameters");
                p->loc_ClientTime                 = qglGetUniformLocation(p->program, "ClientTime");
@@ -1303,6 +1336,7 @@ static void R_GLSL_CompilePermutation(r_glsl_permutation_t *p, unsigned int mode
                p->tex_Texture_ReflectMask = -1;
                p->tex_Texture_ReflectCube = -1;
                p->tex_Texture_BounceGrid = -1;
+               p->tex_Texture_LUT = -1;
                // bind the texture samplers in use
                sampler = 0;
                if (p->loc_Texture_First           >= 0) {p->tex_Texture_First            = sampler;qglUniform1i(p->loc_Texture_First           , sampler);sampler++;}
@@ -1335,6 +1369,7 @@ static void R_GLSL_CompilePermutation(r_glsl_permutation_t *p, unsigned int mode
                if (p->loc_Texture_ReflectMask     >= 0) {p->tex_Texture_ReflectMask      = sampler;qglUniform1i(p->loc_Texture_ReflectMask     , sampler);sampler++;}
                if (p->loc_Texture_ReflectCube     >= 0) {p->tex_Texture_ReflectCube      = sampler;qglUniform1i(p->loc_Texture_ReflectCube     , sampler);sampler++;}
                if (p->loc_Texture_BounceGrid      >= 0) {p->tex_Texture_BounceGrid       = sampler;qglUniform1i(p->loc_Texture_BounceGrid      , sampler);sampler++;}
+               if (p->loc_Texture_LUT             >= 0) {p->tex_Texture_LUT              = sampler;qglUniform1i(p->loc_Texture_LUT             , sampler);sampler++;}
                // get the uniform block indices so we can bind them
                p->ubiloc_Skeletal_Transform12_UniformBlock = -1;
 #ifndef USE_GLES2 /* FIXME: GLES3 only */
@@ -1496,6 +1531,8 @@ void R_SetupShader_Generic(rtexture_t *t, qboolean usegamma, qboolean notrippy,
                        R_Mesh_TexBind(r_glsl_permutation->tex_Texture_First, t);
                if (r_glsl_permutation->tex_Texture_GammaRamps >= 0)
                        R_Mesh_TexBind(r_glsl_permutation->tex_Texture_GammaRamps, r_texture_gammaramps);
+               if (r_glsl_permutation->tex_Texture_LUT >= 0)
+                       R_Mesh_TexBind(r_glsl_permutation->tex_Texture_LUT, r_texture_lut);
                break;
        }
 }
@@ -2057,6 +2094,7 @@ void R_SetupShader_Surface(const float rtlightambient[3], const float rtlightdif
                if (r_glsl_permutation->tex_Texture_First           >= 0) R_Mesh_TexBind(r_glsl_permutation->tex_Texture_First            , r_texture_white                                     );
                if (r_glsl_permutation->tex_Texture_Second          >= 0) R_Mesh_TexBind(r_glsl_permutation->tex_Texture_Second           , r_texture_white                                     );
                if (r_glsl_permutation->tex_Texture_GammaRamps      >= 0) R_Mesh_TexBind(r_glsl_permutation->tex_Texture_GammaRamps       , r_texture_gammaramps                                );
+               if (r_glsl_permutation->tex_Texture_LUT             >= 0) R_Mesh_TexBind(r_glsl_permutation->tex_Texture_LUT              , r_texture_lut                                       );
                if (r_glsl_permutation->tex_Texture_Normal          >= 0) R_Mesh_TexBind(r_glsl_permutation->tex_Texture_Normal           , t->nmaptexture                       );
                if (r_glsl_permutation->tex_Texture_Color           >= 0) R_Mesh_TexBind(r_glsl_permutation->tex_Texture_Color            , t->basetexture                       );
                if (r_glsl_permutation->tex_Texture_Gloss           >= 0) R_Mesh_TexBind(r_glsl_permutation->tex_Texture_Gloss            , t->glosstexture                      );
@@ -3100,6 +3138,8 @@ static void gl_main_start(void)
        r_texture_normalizationcube = NULL;
        r_texture_fogattenuation = NULL;
        r_texture_fogheighttexture = NULL;
+       r_texture_lut = NULL;
+       r_texture_lut_default = NULL;
        r_texture_gammaramps = NULL;
        r_texture_numcubemaps = 0;
        r_uniformbufferalignment = 32;
@@ -3147,6 +3187,7 @@ static void gl_main_start(void)
        R_BuildNoTexture();
        R_BuildWhiteCube();
        R_BuildNormalizationCube();
+       R_BuildDefaultLUT();
        r_texture_fogattenuation = NULL;
        r_texture_fogheighttexture = NULL;
        r_texture_gammaramps = NULL;
@@ -3232,6 +3273,8 @@ static void gl_main_shutdown(void)
        r_texture_normalizationcube = NULL;
        r_texture_fogattenuation = NULL;
        r_texture_fogheighttexture = NULL;
+       r_texture_lut = NULL;
+       r_texture_lut_default = NULL;
        r_texture_gammaramps = NULL;
        r_texture_numcubemaps = 0;
        //r_texture_fogintensity = NULL;
@@ -3396,6 +3439,7 @@ void GL_Main_Init(void)
        Cvar_RegisterVariable(&r_glsl_offsetmapping_lod);
        Cvar_RegisterVariable(&r_glsl_offsetmapping_lod_distance);
        Cvar_RegisterVariable(&r_glsl_postprocess);
+       Cvar_RegisterVariable(&r_glsl_postprocess_color_lut);
        Cvar_RegisterVariable(&r_glsl_postprocess_uservec1);
        Cvar_RegisterVariable(&r_glsl_postprocess_uservec2);
        Cvar_RegisterVariable(&r_glsl_postprocess_uservec3);
@@ -5457,6 +5501,7 @@ static void R_BlendView(int viewfbo, rtexture_t *viewdepthtexture, rtexture_t *v
                if (r_glsl_permutation->tex_Texture_First           >= 0) R_Mesh_TexBind(r_glsl_permutation->tex_Texture_First     , viewtexture);
                if (r_glsl_permutation->tex_Texture_Second          >= 0) R_Mesh_TexBind(r_glsl_permutation->tex_Texture_Second    , bloomtexture);
                if (r_glsl_permutation->tex_Texture_GammaRamps      >= 0) R_Mesh_TexBind(r_glsl_permutation->tex_Texture_GammaRamps, r_texture_gammaramps       );
+               if (r_glsl_permutation->tex_Texture_LUT             >= 0) R_Mesh_TexBind(r_glsl_permutation->tex_Texture_LUT,        r_texture_lut       );
                if (r_glsl_permutation->loc_ViewTintColor           >= 0) qglUniform4f(r_glsl_permutation->loc_ViewTintColor     , r_refdef.viewblend[0], r_refdef.viewblend[1], r_refdef.viewblend[2], r_refdef.viewblend[3]);
                if (r_glsl_permutation->loc_PixelSize               >= 0) qglUniform2f(r_glsl_permutation->loc_PixelSize         , 1.0/r_fb.screentexturewidth, 1.0/r_fb.screentextureheight);
                if (r_glsl_permutation->loc_UserVec1                >= 0) qglUniform4f(r_glsl_permutation->loc_UserVec1          , uservecs[0][0], uservecs[0][1], uservecs[0][2], uservecs[0][3]);
@@ -5602,6 +5647,21 @@ void R_UpdateVariables(void)
        case RENDERPATH_GL32:
                r_gpuskeletal = r_glsl_skeletal.integer && !r_showsurfaces.integer;
        case RENDERPATH_GLES2:
+               if (r_glsl_postprocess.integer)
+               {
+                       if (r_glsl_postprocess_color_lut.string[0])
+                       {
+                               r_texture_lut_pic = Draw_CachePic_Flags(r_glsl_postprocess_color_lut.string, CACHEPICFLAG_NOTPERSISTENT | CACHEPICFLAG_LINEAR);
+                               if (r_texture_lut_pic)
+                                       r_texture_lut = Draw_GetPicTexture(r_texture_lut_pic);
+                               else
+                                       r_texture_lut = r_texture_lut_default;
+                       }
+                       else
+                       {
+                               r_texture_lut = r_texture_lut_default;
+                       }
+               }
                if(!vid_gammatables_trivial)
                {
                        if(!r_texture_gammaramps || vid_gammatables_serial != r_texture_gammaramps_serial)

diff --git a/shader_glsl.h b/shader_glsl.h
index 11ec83dcde56c6c7ce93e78cd9f536f9e1bb6e80..fff9af5fefc2a5d97134b08c14d2af8c81b83c45 100644 (file)
--- a/shader_glsl.h
+++ b/shader_glsl.h
@@ -249,6 +249,7 @@
 "// uniform mediump vec4 UserVec4;\n",
 "uniform mediump float ColorFringe;\n",
 "// uniform highp float ClientTime;\n",
+"// uniform sampler2D Texture_LUT;\n",
 "uniform mediump vec2 PixelSize;\n",
 "\n",
 "#ifdef USEFXAA\n",