use hash lookups on shader permutations to greatly reduce memory usage

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@9259 d7cf8633-e32d-0410-b094-e92efae38249

diff --git a/gl_rmain.c b/gl_rmain.c
index 6bb40f4a1ae8cb0c1a4e57e370fc4091ab18d603..83d0faaa62d94b06c13df57d6ce0560607201f06 100644 (file)
--- a/gl_rmain.c
+++ b/gl_rmain.c
@@ -1550,8 +1550,14 @@ shadermodeinfo_t shadermodeinfo[SHADERMODE_COUNT] =
        {"glsl/default.glsl", NULL, "glsl/default.glsl", "#define MODE_SHOWDEPTH\n", " showdepth"},
 };
 
+struct r_glsl_permutation_s;
 typedef struct r_glsl_permutation_s
 {
+       /// hash lookup data
+       struct r_glsl_permutation_s *hashnext;
+       unsigned int mode;
+       unsigned int permutation;
+
        /// indicates if we have tried compiling this permutation already
        qboolean compiled;
        /// 0 if compilation failed
@@ -1620,10 +1626,39 @@ typedef struct r_glsl_permutation_s
 }
 r_glsl_permutation_t;
 
+#define SHADERPERMUTATION_HASHSIZE 4096
+
 /// information about each possible shader permutation
-r_glsl_permutation_t r_glsl_permutations[SHADERMODE_COUNT][SHADERPERMUTATION_LIMIT];
+r_glsl_permutation_t *r_glsl_permutationhash[SHADERMODE_COUNT][SHADERPERMUTATION_HASHSIZE];
 /// currently selected permutation
 r_glsl_permutation_t *r_glsl_permutation;
+/// storage for permutations linked in the hash table
+memexpandablearray_t r_glsl_permutationarray;
+
+static r_glsl_permutation_t *R_GLSL_FindPermutation(unsigned int mode, unsigned int permutation)
+{
+       //unsigned int hashdepth = 0;
+       unsigned int hashindex = (permutation * 0x1021) & (SHADERPERMUTATION_HASHSIZE - 1);
+       r_glsl_permutation_t *p;
+       for (p = r_glsl_permutationhash[mode][hashindex];p;p = p->hashnext)
+       {
+               if (p->mode == mode && p->permutation == permutation)
+               {
+                       //if (hashdepth > 10)
+                       //      Con_Printf("R_GLSL_FindPermutation: Warning: %i:%i has hashdepth %i\n", mode, permutation, hashdepth);
+                       return p;
+               }
+               //hashdepth++;
+       }
+       p = (r_glsl_permutation_t*)Mem_ExpandableArray_AllocRecord(&r_glsl_permutationarray);
+       p->mode = mode;
+       p->permutation = permutation;
+       p->hashnext = r_glsl_permutationhash[mode][hashindex];
+       r_glsl_permutationhash[mode][hashindex] = p;
+       //if (hashdepth > 10)
+       //      Con_Printf("R_GLSL_FindPermutation: Warning: %i:%i has hashdepth %i\n", mode, permutation, hashdepth);
+       return p;
+}
 
 static char *R_GLSL_GetText(const char *filename, qboolean printfromdisknotice)
 {
@@ -1645,11 +1680,10 @@ static char *R_GLSL_GetText(const char *filename, qboolean printfromdisknotice)
        return shaderstring;
 }
 
-static void R_GLSL_CompilePermutation(unsigned int mode, unsigned int permutation)
+static void R_GLSL_CompilePermutation(r_glsl_permutation_t *p, unsigned int mode, unsigned int permutation)
 {
        int i;
        shadermodeinfo_t *modeinfo = shadermodeinfo + mode;
-       r_glsl_permutation_t *p = &r_glsl_permutations[mode][permutation];
        int vertstrings_count = 0;
        int geomstrings_count = 0;
        int fragstrings_count = 0;
@@ -1827,13 +1861,18 @@ static void R_GLSL_CompilePermutation(unsigned int mode, unsigned int permutatio
 
 void R_GLSL_Restart_f(void)
 {
-       unsigned int mode;
-       unsigned int permutation;
-       for (mode = 0;mode < SHADERMODE_COUNT;mode++)
-               for (permutation = 0;permutation < SHADERPERMUTATION_LIMIT;permutation++)
-                       if (r_glsl_permutations[mode][permutation].program)
-                               GL_Backend_FreeProgram(r_glsl_permutations[mode][permutation].program);
-       memset(r_glsl_permutations, 0, sizeof(r_glsl_permutations));
+       unsigned int i, limit;
+       r_glsl_permutation_t *p;
+       limit = Mem_ExpandableArray_IndexRange(&r_glsl_permutationarray);
+       for (i = 0;i < limit;i++)
+       {
+               if ((p = (r_glsl_permutation_t*)Mem_ExpandableArray_RecordAtIndex(&r_glsl_permutationarray, i)))
+               {
+                       GL_Backend_FreeProgram(p->program);
+                       Mem_ExpandableArray_FreeRecord(&r_glsl_permutationarray, (void*)p);
+               }
+       }
+       memset(r_glsl_permutationhash, 0, sizeof(r_glsl_permutationhash));
 }
 
 void R_GLSL_DumpShader_f(void)
@@ -1862,14 +1901,14 @@ void R_GLSL_DumpShader_f(void)
 
 void R_SetupShader_SetPermutation(unsigned int mode, unsigned int permutation)
 {
-       r_glsl_permutation_t *perm = &r_glsl_permutations[mode][permutation];
+       r_glsl_permutation_t *perm = R_GLSL_FindPermutation(mode, permutation);
        if (r_glsl_permutation != perm)
        {
                r_glsl_permutation = perm;
                if (!r_glsl_permutation->program)
                {
                        if (!r_glsl_permutation->compiled)
-                               R_GLSL_CompilePermutation(mode, permutation);
+                               R_GLSL_CompilePermutation(perm, mode, permutation);
                        if (!r_glsl_permutation->program)
                        {
                                // remove features until we find a valid permutation
@@ -1881,9 +1920,9 @@ void R_SetupShader_SetPermutation(unsigned int mode, unsigned int permutation)
                                        if (!(permutation & j))
                                                continue;
                                        permutation -= j;
-                                       r_glsl_permutation = &r_glsl_permutations[mode][permutation];
+                                       r_glsl_permutation = R_GLSL_FindPermutation(mode, permutation);
                                        if (!r_glsl_permutation->compiled)
-                                               R_GLSL_CompilePermutation(mode, permutation);
+                                               R_GLSL_CompilePermutation(perm, mode, permutation);
                                        if (r_glsl_permutation->program)
                                                break;
                                }
@@ -2691,7 +2730,8 @@ void gl_main_start(void)
        //r_texture_fogintensity = NULL;
        memset(&r_bloomstate, 0, sizeof(r_bloomstate));
        memset(&r_waterstate, 0, sizeof(r_waterstate));
-       memset(r_glsl_permutations, 0, sizeof(r_glsl_permutations));
+       memset(r_glsl_permutationhash, 0, sizeof(r_glsl_permutationhash));
+       Mem_ExpandableArray_NewArray(&r_glsl_permutationarray, r_main_mempool, sizeof(r_glsl_permutation_t), 256);
        memset(&r_svbsp, 0, sizeof (r_svbsp));
 
        r_refdef.fogmasktable_density = 0;