obs-studio/libobs-opengl/gl-shaderparser.c

665 lines
18 KiB
C

/******************************************************************************
Copyright (C) 2013 by Hugh Bailey <obs.jim@gmail.com>
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
******************************************************************************/
#include "gl-subsystem.h"
#include "gl-shaderparser.h"
static void gl_write_function_contents(struct gl_shader_parser *glsp,
struct cf_token **p_token, const char *end);
static inline struct shader_var *sp_getparam(struct gl_shader_parser *glsp,
struct cf_token *token)
{
size_t i;
for (i = 0; i < glsp->parser.params.num; i++) {
struct shader_var *param = glsp->parser.params.array+i;
if (strref_cmp(&token->str, param->name) == 0)
return param;
}
return NULL;
}
static inline size_t sp_getsampler(struct gl_shader_parser *glsp,
struct cf_token *token)
{
size_t i;
for (i = 0; i < glsp->parser.samplers.num; i++) {
struct shader_sampler *sampler = glsp->parser.samplers.array+i;
if (strref_cmp(&token->str, sampler->name) == 0)
return i;
}
return -1;
}
static inline int cmp_type(const char *name, const size_t name_len,
const char *type, const size_t type_len)
{
size_t min_len = (name_len < type_len) ? type_len : name_len;
return astrcmp_n(name, type, min_len);
}
static bool gl_write_type_n(struct gl_shader_parser *glsp,
const char *type, size_t len)
{
if (cmp_type(type, len, "float2", 6) == 0)
dstr_cat(&glsp->gl_string, "vec2");
else if (cmp_type(type, len, "float3", 6) == 0)
dstr_cat(&glsp->gl_string, "vec3");
else if (cmp_type(type, len, "float4", 6) == 0)
dstr_cat(&glsp->gl_string, "vec4");
else if (cmp_type(type, len, "float3x3", 8) == 0)
dstr_cat(&glsp->gl_string, "mat3x3");
else if (cmp_type(type, len, "float3x4", 8) == 0)
dstr_cat(&glsp->gl_string, "mat3x4");
else if (cmp_type(type, len, "float4x4", 8) == 0)
dstr_cat(&glsp->gl_string, "mat4x4");
else if (cmp_type(type, len, "texture2d", 9) == 0)
dstr_cat(&glsp->gl_string, "sampler2D");
else if (cmp_type(type, len, "texture3d", 9) == 0)
dstr_cat(&glsp->gl_string, "sampler3D");
else if (cmp_type(type, len, "texture_cube", 12) == 0)
dstr_cat(&glsp->gl_string, "samplerCube");
else if (cmp_type(type, len, "texture_rect", 12) == 0)
dstr_cat(&glsp->gl_string, "sampler2DRect");
else
return false;
return true;
}
static inline void gl_write_type(struct gl_shader_parser *glsp,
const char *type)
{
if (!gl_write_type_n(glsp, type, strlen(type)))
dstr_cat(&glsp->gl_string, type);
}
static inline bool gl_write_type_token(struct gl_shader_parser *glsp,
struct cf_token *token)
{
return gl_write_type_n(glsp, token->str.array, token->str.len);
}
static void gl_write_var(struct gl_shader_parser *glsp, struct shader_var *var)
{
if (var->var_type == SHADER_VAR_UNIFORM)
dstr_cat(&glsp->gl_string, "uniform ");
else if (var->var_type == SHADER_VAR_CONST)
dstr_cat(&glsp->gl_string, "const ");
gl_write_type(glsp, var->type);
dstr_cat(&glsp->gl_string, " ");
dstr_cat(&glsp->gl_string, var->name);
}
static inline void gl_write_params(struct gl_shader_parser *glsp)
{
size_t i;
for (i = 0; i < glsp->parser.params.num; i++) {
struct shader_var *var = glsp->parser.params.array+i;
gl_write_var(glsp, var);
dstr_cat(&glsp->gl_string, ";\n");
}
dstr_cat(&glsp->gl_string, "\n");
}
static void gl_write_storage_var(struct gl_shader_parser *glsp,
struct shader_var *var, bool input, const char *prefix);
/* unwraps a structure that's used for input/output */
static void gl_unwrap_storage_struct(struct gl_shader_parser *glsp,
struct shader_struct *st, const char *name, bool input,
const char *prefix)
{
struct dstr prefix_str;
size_t i;
dstr_init(&prefix_str);
if (prefix)
dstr_copy(&prefix_str, prefix);
dstr_cat(&prefix_str, name);
dstr_cat(&prefix_str, "_");
for (i = 0; i < st->vars.num; i++) {
struct shader_var *st_var = st->vars.array+i;
gl_write_storage_var(glsp, st_var, input, prefix_str.array);
}
dstr_free(&prefix_str);
}
static void gl_write_storage_var(struct gl_shader_parser *glsp,
struct shader_var *var, bool input, const char *prefix)
{
struct shader_struct *st = shader_parser_getstruct(&glsp->parser,
var->type);
if (st) {
gl_unwrap_storage_struct(glsp, st, var->name, input, prefix);
} else {
struct gl_parser_attrib attrib;
gl_parser_attrib_init(&attrib);
dstr_cat(&glsp->gl_string, input ? "in " : "out ");
if (prefix)
dstr_cat(&attrib.name, prefix);
dstr_cat(&attrib.name, var->name);
gl_write_type(glsp, var->type);
dstr_cat(&glsp->gl_string, " ");
dstr_cat_dstr(&glsp->gl_string, &attrib.name);
dstr_cat(&glsp->gl_string, ";\n");
attrib.input = input;
attrib.mapping = var->mapping;
da_push_back(glsp->attribs, &attrib);
}
}
static inline void gl_write_inputs(struct gl_shader_parser *glsp,
struct shader_func *main)
{
size_t i;
for (i = 0; i < main->params.num; i++)
gl_write_storage_var(glsp, main->params.array+i, true,
"inputval_");
dstr_cat(&glsp->gl_string, "\n");
}
static void gl_write_outputs(struct gl_shader_parser *glsp,
struct shader_func *main)
{
struct shader_var var = {0};
var.type = main->return_type;
var.name = "outputval";
if (main->mapping)
var.mapping = main->mapping;
gl_write_storage_var(glsp, &var, false, NULL);
dstr_cat(&glsp->gl_string, "\n");
}
static void gl_write_struct(struct gl_shader_parser *glsp,
struct shader_struct *st)
{
size_t i;
dstr_cat(&glsp->gl_string, "struct ");
dstr_cat(&glsp->gl_string, st->name);
dstr_cat(&glsp->gl_string, " {\n");
for (i = 0; i < st->vars.num; i++) {
struct shader_var *var = st->vars.array+i;
dstr_cat(&glsp->gl_string, "\t");
gl_write_var(glsp, var);
dstr_cat(&glsp->gl_string, ";\n");
}
dstr_cat(&glsp->gl_string, "};\n\n");
}
static void gl_write_interface_block(struct gl_shader_parser *glsp)
{
if (glsp->type == GS_SHADER_VERTEX) {
dstr_cat(&glsp->gl_string, "out gl_PerVertex {\n"
"\tvec4 gl_Position;\n};\n\n");
}
}
static inline void gl_write_structs(struct gl_shader_parser *glsp)
{
size_t i;
for (i = 0; i < glsp->parser.structs.num; i++) {
struct shader_struct *st = glsp->parser.structs.array+i;
gl_write_struct(glsp, st);
}
}
/*
* NOTE: HLSL-> GLSL intrinsic conversions
* atan2 -> atan
* clip -> (unsupported)
* ddx -> dFdx
* ddy -> dFdy
* fmod -> mod (XXX: these are different if sign is negative)
* frac -> fract
* lerp -> mix
* lit -> (unsupported)
* log10 -> (unsupported)
* mul -> (change to operator)
* rsqrt -> inversesqrt
* saturate -> (use clamp)
* tex* -> texture
* tex*grad -> textureGrad
* tex*lod -> textureLod
* tex*bias -> (use optional 'bias' value)
* tex*proj -> textureProj
*
* All else can be left as-is
*/
static bool gl_write_mul(struct gl_shader_parser *glsp,
struct cf_token **p_token)
{
struct cf_parser *cfp = &glsp->parser.cfp;
cfp->cur_token = *p_token;
if (!cf_next_token(cfp)) return false;
if (!cf_token_is(cfp, "(")) return false;
dstr_cat(&glsp->gl_string, "(");
gl_write_function_contents(glsp, &cfp->cur_token, ",");
dstr_cat(&glsp->gl_string, ") * (");
cf_next_token(cfp);
gl_write_function_contents(glsp, &cfp->cur_token, ")");
dstr_cat(&glsp->gl_string, "))");
*p_token = cfp->cur_token;
return true;
}
static bool gl_write_saturate(struct gl_shader_parser *glsp,
struct cf_token **p_token)
{
struct cf_parser *cfp = &glsp->parser.cfp;
cfp->cur_token = *p_token;
if (!cf_next_token(cfp)) return false;
if (!cf_token_is(cfp, "(")) return false;
dstr_cat(&glsp->gl_string, "clamp");
gl_write_function_contents(glsp, &cfp->cur_token, ")");
dstr_cat(&glsp->gl_string, ", 0.0, 1.0)");
*p_token = cfp->cur_token;
return true;
}
static inline bool gl_write_texture_call(struct gl_shader_parser *glsp,
struct shader_var *var, const char *call)
{
struct cf_parser *cfp = &glsp->parser.cfp;
size_t sampler_id = (size_t)-1;
if (!cf_next_token(cfp)) return false;
if (!cf_token_is(cfp, "(")) return false;
if (!cf_next_token(cfp)) return false;
sampler_id = sp_getsampler(glsp, cfp->cur_token);
if (sampler_id == (size_t)-1) return false;
if (!cf_next_token(cfp)) return false;
if (!cf_token_is(cfp, ",")) return false;
var->gl_sampler_id = sampler_id;
dstr_cat(&glsp->gl_string, call);
dstr_cat(&glsp->gl_string, "(");
dstr_cat(&glsp->gl_string, var->name);
dstr_cat(&glsp->gl_string, ", ");
return true;
}
/* processes texture.Sample(sampler, texcoord) */
static bool gl_write_texture_code(struct gl_shader_parser *glsp,
struct cf_token **p_token, struct shader_var *var)
{
struct cf_parser *cfp = &glsp->parser.cfp;
bool written = false;
cfp->cur_token = *p_token;
if (!cf_next_token(cfp)) return false;
if (!cf_token_is(cfp, ".")) return false;
if (!cf_next_token(cfp)) return false;
if (cf_token_is(cfp, "Sample"))
written = gl_write_texture_call(glsp, var, "texture");
else if (cf_token_is(cfp, "SampleBias"))
written = gl_write_texture_call(glsp, var, "texture");
else if (cf_token_is(cfp, "SampleGrad"))
written = gl_write_texture_call(glsp, var, "textureGrad");
else if (cf_token_is(cfp, "SampleLevel"))
written = gl_write_texture_call(glsp, var, "textureLod");
if (!written)
return false;
if (!cf_next_token(cfp)) return false;
gl_write_function_contents(glsp, &cfp->cur_token, ")");
dstr_cat(&glsp->gl_string, ")");
*p_token = cfp->cur_token;
return true;
}
static bool gl_write_intrinsic(struct gl_shader_parser *glsp,
struct cf_token **p_token)
{
struct cf_token *token = *p_token;
bool written = true;
if (strref_cmp(&token->str, "atan2") == 0) {
dstr_cat(&glsp->gl_string, "atan2");
} else if (strref_cmp(&token->str, "ddx") == 0) {
dstr_cat(&glsp->gl_string, "dFdx");
} else if (strref_cmp(&token->str, "ddy") == 0) {
dstr_cat(&glsp->gl_string, "dFdy");
} else if (strref_cmp(&token->str, "frac") == 0) {
dstr_cat(&glsp->gl_string, "fract");
} else if (strref_cmp(&token->str, "lerp") == 0) {
dstr_cat(&glsp->gl_string, "mix");
} else if (strref_cmp(&token->str, "fmod") == 0) {
dstr_cat(&glsp->gl_string, "mod");
} else if (strref_cmp(&token->str, "rsqrt") == 0) {
dstr_cat(&glsp->gl_string, "inversesqrt");
} else if (strref_cmp(&token->str, "saturate") == 0) {
written = gl_write_saturate(glsp, &token);
} else if (strref_cmp(&token->str, "mul") == 0) {
written = gl_write_mul(glsp, &token);
} else {
struct shader_var *var = sp_getparam(glsp, token);
if (var && astrcmp_n(var->type, "texture", 7) == 0)
written = gl_write_texture_code(glsp, &token, var);
else
written = false;
}
if (written)
*p_token = token;
return written;
}
static void gl_write_function_contents(struct gl_shader_parser *glsp,
struct cf_token **p_token, const char *end)
{
struct cf_token *token = *p_token;
if (token->type != CFTOKEN_NAME
|| ( !gl_write_type_token(glsp, token)
&& !gl_write_intrinsic(glsp, &token)))
dstr_cat_strref(&glsp->gl_string, &token->str);
while (token->type != CFTOKEN_NONE) {
token++;
if (end && strref_cmp(&token->str, end) == 0)
break;
if (token->type == CFTOKEN_NAME) {
if (!gl_write_type_token(glsp, token) &&
!gl_write_intrinsic(glsp, &token))
dstr_cat_strref(&glsp->gl_string, &token->str);
} else if (token->type == CFTOKEN_OTHER) {
if (*token->str.array == '{')
gl_write_function_contents(glsp, &token, "}");
else if (*token->str.array == '(')
gl_write_function_contents(glsp, &token, ")");
dstr_cat_strref(&glsp->gl_string, &token->str);
} else {
dstr_cat_strref(&glsp->gl_string, &token->str);
}
}
*p_token = token;
}
static void gl_write_function(struct gl_shader_parser *glsp,
struct shader_func *func)
{
size_t i;
struct cf_token *token;
gl_write_type(glsp, func->return_type);
dstr_cat(&glsp->gl_string, " ");
if (strcmp(func->name, "main") == 0)
dstr_cat(&glsp->gl_string, "_main_wrap");
else
dstr_cat(&glsp->gl_string, func->name);
dstr_cat(&glsp->gl_string, "(");
for (i = 0; i < func->params.num; i++) {
struct shader_var *param = func->params.array+i;
if (i > 0)
dstr_cat(&glsp->gl_string, ", ");
gl_write_var(glsp, param);
}
dstr_cat(&glsp->gl_string, ")\n");
token = func->start;
gl_write_function_contents(glsp, &token, "}");
dstr_cat(&glsp->gl_string, "}\n\n");
}
static inline void gl_write_functions(struct gl_shader_parser *glsp)
{
size_t i;
for (i = 0; i < glsp->parser.funcs.num; i++) {
struct shader_func *func = glsp->parser.funcs.array+i;
gl_write_function(glsp, func);
}
}
static inline void gl_write_main_interface_assign(
struct gl_shader_parser *glsp, struct shader_var *var,
const char *src)
{
/* vertex shaders: write gl_Position */
if (glsp->type == GS_SHADER_VERTEX &&
strcmp(var->mapping, "POSITION") == 0) {
dstr_cat(&glsp->gl_string, "\tgl_Position = ");
dstr_cat(&glsp->gl_string, src);
dstr_cat(&glsp->gl_string, var->name);
dstr_cat(&glsp->gl_string, ";\n");
}
}
static void gl_write_main_storage_assign(struct gl_shader_parser *glsp,
struct shader_var *var, const char *dst, const char *src,
bool input)
{
struct shader_struct *st;
struct dstr dst_copy = {0};
char ch_left = input ? '.' : '_';
char ch_right = input ? '_' : '.';
if (dst) {
dstr_copy(&dst_copy, dst);
dstr_cat_ch(&dst_copy, ch_left);
} else {
dstr_copy(&dst_copy, "\t");
}
dstr_cat(&dst_copy, var->name);
st = shader_parser_getstruct(&glsp->parser, var->type);
if (st) {
struct dstr src_copy = {0};
size_t i;
if (src)
dstr_copy(&src_copy, src);
dstr_cat(&src_copy, var->name);
dstr_cat_ch(&src_copy, ch_right);
for (i = 0; i < st->vars.num; i++) {
struct shader_var *st_var = st->vars.array+i;
gl_write_main_storage_assign(glsp, st_var,
dst_copy.array, src_copy.array, input);
}
dstr_free(&src_copy);
} else {
if (!dstr_is_empty(&dst_copy))
dstr_cat_dstr(&glsp->gl_string, &dst_copy);
dstr_cat(&glsp->gl_string, " = ");
if (src)
dstr_cat(&glsp->gl_string, src);
dstr_cat(&glsp->gl_string, var->name);
dstr_cat(&glsp->gl_string, ";\n");
if (!input)
gl_write_main_interface_assign(glsp, var, src);
}
dstr_free(&dst_copy);
}
static inline void gl_write_main_storage_inputs(struct gl_shader_parser *glsp,
struct shader_func *main)
{
gl_write_main_storage_assign(glsp, main->params.array, NULL,
"inputval_", true);
}
static inline void gl_write_main_storage_outputs(struct gl_shader_parser *glsp,
struct shader_func *main)
{
/* we only do this *if* we're writing a struct, because otherwise
* the call to 'main' already does the assignment for us */
if (!main->mapping) {
struct shader_var var = {0};
var.name = "outputval";
var.type = (char*)main->return_type;
dstr_cat(&glsp->gl_string, "\n");
gl_write_main_storage_assign(glsp, &var, NULL, NULL, false);
}
}
static inline void gl_write_main_vars(struct gl_shader_parser *glsp,
struct shader_func *main_func)
{
size_t i;
for (i = 0; i < main_func->params.num; i++) {
dstr_cat(&glsp->gl_string, "\t");
dstr_cat(&glsp->gl_string, main_func->params.array[i].type);
dstr_cat(&glsp->gl_string, " ");
dstr_cat(&glsp->gl_string, main_func->params.array[i].name);
dstr_cat(&glsp->gl_string, ";\n");
}
if (!main_func->mapping) {
dstr_cat(&glsp->gl_string, "\t");
dstr_cat(&glsp->gl_string, main_func->return_type);
dstr_cat(&glsp->gl_string, " outputval;\n\n");
}
}
static inline void gl_write_main_func_call(struct gl_shader_parser *glsp,
struct shader_func *main_func)
{
size_t i;
dstr_cat(&glsp->gl_string, "\n\toutputval = _main_wrap(");
for (i = 0; i < main_func->params.num; i++) {
if (i)
dstr_cat(&glsp->gl_string, ", ");
dstr_cat(&glsp->gl_string, main_func->params.array[i].name);
}
dstr_cat(&glsp->gl_string, ");\n");
}
static void gl_write_main(struct gl_shader_parser *glsp,
struct shader_func *main)
{
dstr_cat(&glsp->gl_string, "void main(void)\n{\n");
gl_write_main_vars(glsp, main);
gl_write_main_storage_inputs(glsp, main);
gl_write_main_func_call(glsp, main);
gl_write_main_storage_outputs(glsp, main);
dstr_cat(&glsp->gl_string, "}\n");
}
/* ugh, don't ask. I'll probably get rid of the need for this function later */
static void gl_rename_attributes(struct gl_shader_parser *glsp)
{
size_t i = 0, input_idx = 0, output_idx = 0;
for (i = 0; i < glsp->attribs.num; i++) {
struct gl_parser_attrib *attrib = glsp->attribs.array+i;
struct dstr new_name = {0};
const char *prefix;
size_t val;
if (attrib->input) {
prefix = glsp->input_prefix;
val = input_idx++;
} else {
prefix = glsp->output_prefix;
val = output_idx++;
}
dstr_printf(&new_name, "%s%u", prefix, (unsigned int)val);
dstr_replace(&glsp->gl_string, attrib->name.array,
new_name.array);
dstr_move(&attrib->name, &new_name);
}
}
static bool gl_shader_buildstring(struct gl_shader_parser *glsp)
{
struct shader_func *main_func;
main_func = shader_parser_getfunc(&glsp->parser, "main");
if (!main_func) {
blog(LOG_ERROR, "function 'main' not found");
return false;
}
dstr_copy(&glsp->gl_string, "#version 150\n\n");
gl_write_params(glsp);
gl_write_inputs(glsp, main_func);
gl_write_outputs(glsp, main_func);
gl_write_interface_block(glsp);
gl_write_structs(glsp);
gl_write_functions(glsp);
gl_write_main(glsp, main_func);
gl_rename_attributes(glsp);
return true;
}
bool gl_shader_parse(struct gl_shader_parser *glsp,
const char *shader_str, const char *file)
{
bool success = shader_parse(&glsp->parser, shader_str, file);
char *str = shader_parser_geterrors(&glsp->parser);
if (str) {
blog(LOG_WARNING, "Shader parser errors/warnings:\n%s\n", str);
bfree(str);
}
if (success)
success = gl_shader_buildstring(glsp);
return success;
}