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mutter/cogl/cogl-blend-string.c
Robert Bragg 54735dec84 Switch use of primitive glib types to c99 equivalents 
The coding style has for a long time said to avoid using redundant glib
data types such as gint or gchar etc because we feel that they make the
code look unnecessarily foreign to developers coming from outside of the
Gnome developer community.

Note: When we tried to find the historical rationale for the types we
just found that they were apparently only added for consistent syntax
highlighting which didn't seem that compelling.

Up until now we have been continuing to use some of the platform
specific type such as gint{8,16,32,64} and gsize but this patch switches
us over to using the standard c99 equivalents instead so we can further
ensure that our code looks familiar to the widest range of C developers
who might potentially contribute to Cogl.

So instead of using the gint{8,16,32,64} and guint{8,16,32,64} types this
switches all Cogl code to instead use the int{8,16,32,64}_t and
uint{8,16,32,64}_t c99 types instead.

Instead of gsize we now use size_t

For now we are not going to use the c99 _Bool type and instead we have
introduced a new CoglBool type to use instead of gboolean.

Reviewed-by: Neil Roberts <neil@linux.intel.com>

(cherry picked from commit 5967dad2400d32ca6319cef6cb572e81bf2c15f0)
2012-08-06 14:27:39 +01:00

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/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2009 Intel Corporation.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*
*
*
* Authors:
* Robert Bragg <robert@linux.intel.com>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdlib.h>
#include <string.h>
#include <glib.h>
#include "cogl-internal.h"
#include "cogl-context-private.h"
#include "cogl-debug.h"
#include "cogl-blend-string.h"
typedef enum _ParserState
{
PARSER_STATE_EXPECT_DEST_CHANNELS,
PARSER_STATE_SCRAPING_DEST_CHANNELS,
PARSER_STATE_EXPECT_FUNCTION_NAME,
PARSER_STATE_SCRAPING_FUNCTION_NAME,
PARSER_STATE_EXPECT_ARG_START,
PARSER_STATE_EXPECT_STATEMENT_END
} ParserState;
typedef enum _ParserArgState
{
PARSER_ARG_STATE_START,
PARSER_ARG_STATE_EXPECT_MINUS,
PARSER_ARG_STATE_EXPECT_COLOR_SRC_NAME,
PARSER_ARG_STATE_SCRAPING_COLOR_SRC_NAME,
PARSER_ARG_STATE_MAYBE_COLOR_MASK,
PARSER_ARG_STATE_SCRAPING_MASK,
PARSER_ARG_STATE_MAYBE_MULT,
PARSER_ARG_STATE_EXPECT_OPEN_PAREN,
PARSER_ARG_STATE_EXPECT_FACTOR,
PARSER_ARG_STATE_MAYBE_SRC_ALPHA_SATURATE,
PARSER_ARG_STATE_MAYBE_MINUS,
PARSER_ARG_STATE_EXPECT_CLOSE_PAREN,
PARSER_ARG_STATE_EXPECT_END
} ParserArgState;
#define DEFINE_COLOR_SOURCE(NAME, NAME_LEN) \
{/*.type = */COGL_BLEND_STRING_COLOR_SOURCE_ ## NAME, \
/*.name = */#NAME, \
/*.name_len = */NAME_LEN}
static CoglBlendStringColorSourceInfo blending_color_sources[] = {
DEFINE_COLOR_SOURCE (SRC_COLOR, 9),
DEFINE_COLOR_SOURCE (DST_COLOR, 9),
DEFINE_COLOR_SOURCE (CONSTANT, 8)
};
static CoglBlendStringColorSourceInfo tex_combine_color_sources[] = {
DEFINE_COLOR_SOURCE (TEXTURE, 7),
/* DEFINE_COLOR_SOURCE (TEXTURE_N, *) - handled manually */
DEFINE_COLOR_SOURCE (PRIMARY, 7),
DEFINE_COLOR_SOURCE (CONSTANT, 8),
DEFINE_COLOR_SOURCE (PREVIOUS, 8)
};
static CoglBlendStringColorSourceInfo tex_combine_texture_n_color_source = {
/*.type = */COGL_BLEND_STRING_COLOR_SOURCE_TEXTURE_N,
/*.name = */"TEXTURE_N",
/*.name_len = */0
};
#undef DEFINE_COLOR_SOURCE
#define DEFINE_FUNCTION(NAME, NAME_LEN, ARGC) \
{ /*.type = */COGL_BLEND_STRING_FUNCTION_ ## NAME, \
/*.name = */#NAME, \
/*.name_len = */NAME_LEN, \
/*.argc = */ARGC }
/* NB: These must be sorted so any name that's a subset of another
* comes later than the longer name. */
static CoglBlendStringFunctionInfo tex_combine_functions[] = {
DEFINE_FUNCTION (REPLACE, 7, 1),
DEFINE_FUNCTION (MODULATE, 8, 2),
DEFINE_FUNCTION (ADD_SIGNED, 10, 2),
DEFINE_FUNCTION (ADD, 3, 2),
DEFINE_FUNCTION (INTERPOLATE, 11, 3),
DEFINE_FUNCTION (SUBTRACT, 8, 2),
DEFINE_FUNCTION (DOT3_RGBA, 9, 2),
DEFINE_FUNCTION (DOT3_RGB, 8, 2)
};
static CoglBlendStringFunctionInfo blend_functions[] = {
DEFINE_FUNCTION (ADD, 3, 2)
};
#undef DEFINE_FUNCTION
GQuark
cogl_blend_string_error_quark (void)
{
return g_quark_from_static_string ("cogl-blend-string-error-quark");
}
void
_cogl_blend_string_split_rgba_statement (CoglBlendStringStatement *statement,
CoglBlendStringStatement *rgb,
CoglBlendStringStatement *a)
{
int i;
memcpy (rgb, statement, sizeof (CoglBlendStringStatement));
memcpy (a, statement, sizeof (CoglBlendStringStatement));
rgb->mask = COGL_BLEND_STRING_CHANNEL_MASK_RGB;
a->mask = COGL_BLEND_STRING_CHANNEL_MASK_ALPHA;
for (i = 0; i < statement->function->argc; i++)
{
CoglBlendStringArgument *arg = &statement->args[i];
CoglBlendStringArgument *rgb_arg = &rgb->args[i];
CoglBlendStringArgument *a_arg = &a->args[i];
if (arg->source.mask == COGL_BLEND_STRING_CHANNEL_MASK_RGBA)
{
rgb_arg->source.mask = COGL_BLEND_STRING_CHANNEL_MASK_RGB;
a_arg->source.mask = COGL_BLEND_STRING_CHANNEL_MASK_ALPHA;
}
if (arg->factor.is_color &&
arg->factor.source.mask == COGL_BLEND_STRING_CHANNEL_MASK_RGBA)
{
rgb_arg->factor.source.mask = COGL_BLEND_STRING_CHANNEL_MASK_RGB;
a_arg->factor.source.mask = COGL_BLEND_STRING_CHANNEL_MASK_ALPHA;
}
}
}
static CoglBool
validate_tex_combine_statements (CoglBlendStringStatement *statements,
int n_statements,
GError **error)
{
int i, j;
const char *error_string;
CoglBlendStringError detail = COGL_BLEND_STRING_ERROR_INVALID_ERROR;
for (i = 0; i < n_statements; i++)
{
for (j = 0; j < statements[i].function->argc; j++)
{
CoglBlendStringArgument *arg = &statements[i].args[j];
if (arg->source.is_zero)
{
error_string = "You can't use the constant '0' as a texture "
"combine argument";
goto error;
}
if (!arg->factor.is_one)
{
error_string = "Argument factors are only relevant to blending "
"not texture combining";
goto error;
}
}
}
return TRUE;
error:
g_set_error (error,
COGL_BLEND_STRING_ERROR,
detail,
"Invalid texture combine string: %s",
error_string);
if (COGL_DEBUG_ENABLED (COGL_DEBUG_BLEND_STRINGS))
{
g_debug ("Invalid texture combine string: %s",
error_string);
}
return FALSE;
}
static CoglBool
validate_blend_statements (CoglBlendStringStatement *statements,
int n_statements,
GError **error)
{
int i, j;
const char *error_string;
CoglBlendStringError detail = COGL_BLEND_STRING_ERROR_INVALID_ERROR;
_COGL_GET_CONTEXT (ctx, 0);
if (ctx->driver == COGL_DRIVER_GL)
{
if (n_statements == 2)
{
/* glBlendEquationSeperate is GL 2.0 only */
if (!ctx->glBlendEquationSeparate &&
statements[0].function->type != statements[1].function->type)
{
error_string = "Separate blend functions for the RGB an A "
"channels isn't supported by the driver";
detail = COGL_BLEND_STRING_ERROR_GPU_UNSUPPORTED_ERROR;
goto error;
}
}
}
else if (ctx->driver == COGL_DRIVER_GLES1)
{
if (n_statements != 1)
{
error_string = "Separate blend functions for the RGB an A "
"channels isn't supported by the GLES 1";
detail = COGL_BLEND_STRING_ERROR_GPU_UNSUPPORTED_ERROR;
goto error;
}
}
for (i = 0; i < n_statements; i++)
for (j = 0; j < statements[i].function->argc; j++)
{
CoglBlendStringArgument *arg = &statements[i].args[j];
if (arg->source.is_zero)
continue;
if ((j == 0 &&
arg->source.info->type !=
COGL_BLEND_STRING_COLOR_SOURCE_SRC_COLOR)
|| (j == 1 &&
arg->source.info->type !=
COGL_BLEND_STRING_COLOR_SOURCE_DST_COLOR))
{
error_string = "For blending you must always use SRC_COLOR "
"for arg0 and DST_COLOR for arg1";
goto error;
}
if (ctx->driver == COGL_DRIVER_GLES1 &&
arg->factor.is_color &&
(arg->factor.source.info->type ==
COGL_BLEND_STRING_COLOR_SOURCE_CONSTANT))
{
error_string = "GLES Doesn't support constant blend factors";
detail = COGL_BLEND_STRING_ERROR_GPU_UNSUPPORTED_ERROR;
goto error;
}
}
return TRUE;
error:
g_set_error (error,
COGL_BLEND_STRING_ERROR,
detail,
"Invalid blend string: %s",
error_string);
return FALSE;
}
static CoglBool
validate_statements_for_context (CoglBlendStringStatement *statements,
int n_statements,
CoglBlendStringContext context,
GError **error)
{
const char *error_string;
if (n_statements == 1)
{
if (statements[0].mask == COGL_BLEND_STRING_CHANNEL_MASK_ALPHA)
{
error_string = "You need to also give a blend statement for the RGB"
"channels";
goto error;
}
else if (statements[0].mask == COGL_BLEND_STRING_CHANNEL_MASK_RGB)
{
error_string = "You need to also give a blend statement for the "
"Alpha channel";
goto error;
}
}
if (context == COGL_BLEND_STRING_CONTEXT_BLENDING)
return validate_blend_statements (statements, n_statements, error);
else
return validate_tex_combine_statements (statements, n_statements, error);
error:
g_set_error (error,
COGL_BLEND_STRING_ERROR,
COGL_BLEND_STRING_ERROR_INVALID_ERROR,
"Invalid %s string: %s",
context == COGL_BLEND_STRING_CONTEXT_BLENDING ?
"blend" : "texture combine",
error_string);
if (COGL_DEBUG_ENABLED (COGL_DEBUG_BLEND_STRINGS))
{
g_debug ("Invalid %s string: %s",
context == COGL_BLEND_STRING_CONTEXT_BLENDING ?
"blend" : "texture combine",
error_string);
}
return FALSE;
}
static void
print_argument (CoglBlendStringArgument *arg)
{
const char *mask_names[] = {
"RGB",
"A",
"RGBA"
};
g_print (" Arg:\n");
g_print (" is zero = %s\n", arg->source.is_zero ? "yes" : "no");
if (!arg->source.is_zero)
{
g_print (" color source = %s\n", arg->source.info->name);
g_print (" one minus = %s\n", arg->source.one_minus ? "yes" : "no");
g_print (" mask = %s\n", mask_names[arg->source.mask]);
g_print (" texture = %d\n", arg->source.texture);
g_print ("\n");
g_print (" factor is_one = %s\n", arg->factor.is_one ? "yes" : "no");
g_print (" factor is_src_alpha_saturate = %s\n",
arg->factor.is_src_alpha_saturate ? "yes" : "no");
g_print (" factor is_color = %s\n", arg->factor.is_color ? "yes" : "no");
if (arg->factor.is_color)
{
g_print (" factor color:is zero = %s\n",
arg->factor.source.is_zero ? "yes" : "no");
g_print (" factor color:color source = %s\n",
arg->factor.source.info->name);
g_print (" factor color:one minus = %s\n",
arg->factor.source.one_minus ? "yes" : "no");
g_print (" factor color:mask = %s\n",
mask_names[arg->factor.source.mask]);
g_print (" factor color:texture = %d\n",
arg->factor.source.texture);
}
}
}
static void
print_statement (int num, CoglBlendStringStatement *statement)
{
const char *mask_names[] = {
"RGB",
"A",
"RGBA"
};
int i;
g_print ("Statement %d:\n", num);
g_print (" Destination channel mask = %s\n",
mask_names[statement->mask]);
g_print (" Function = %s\n", statement->function->name);
for (i = 0; i < statement->function->argc; i++)
print_argument (&statement->args[i]);
}
static const CoglBlendStringFunctionInfo *
get_function_info (const char *mark,
const char *p,
CoglBlendStringContext context)
{
size_t len = p - mark;
CoglBlendStringFunctionInfo *functions;
size_t array_len;
int i;
if (context == COGL_BLEND_STRING_CONTEXT_BLENDING)
{
functions = blend_functions;
array_len = G_N_ELEMENTS (blend_functions);
}
else
{
functions = tex_combine_functions;
array_len = G_N_ELEMENTS (tex_combine_functions);
}
for (i = 0; i < array_len; i++)
{
if (len >= functions[i].name_len
&& strncmp (mark, functions[i].name, functions[i].name_len) == 0)
return &functions[i];
}
return NULL;
}
static const CoglBlendStringColorSourceInfo *
get_color_src_info (const char *mark,
const char *p,
CoglBlendStringContext context)
{
size_t len = p - mark;
CoglBlendStringColorSourceInfo *sources;
size_t array_len;
int i;
if (context == COGL_BLEND_STRING_CONTEXT_BLENDING)
{
sources = blending_color_sources;
array_len = G_N_ELEMENTS (blending_color_sources);
}
else
{
sources = tex_combine_color_sources;
array_len = G_N_ELEMENTS (tex_combine_color_sources);
}
if (len >= 8 &&
strncmp (mark, "TEXTURE_", 8) == 0 &&
g_ascii_isdigit (mark[8]))
{
return &tex_combine_texture_n_color_source;
}
for (i = 0; i < array_len; i++)
{
if (len >= sources[i].name_len
&& strncmp (mark, sources[i].name, sources[i].name_len) == 0)
return &sources[i];
}
return NULL;
}
static CoglBool
is_symbol_char (const char c)
{
return (g_ascii_isalpha (c) || c == '_') ? TRUE : FALSE;
}
static CoglBool
is_alphanum_char (const char c)
{
return (g_ascii_isalnum (c) || c == '_') ? TRUE : FALSE;
}
static CoglBool
parse_argument (const char *string, /* original user string */
const char **ret_p, /* start of argument IN:OUT */
const CoglBlendStringStatement *statement,
int current_arg,
CoglBlendStringArgument *arg, /* OUT */
CoglBlendStringContext context,
GError **error)
{
const char *p = *ret_p;
const char *mark = NULL;
const char *error_string = NULL;
ParserArgState state = PARSER_ARG_STATE_START;
CoglBool parsing_factor = FALSE;
CoglBool implicit_factor_brace;
arg->source.is_zero = FALSE;
arg->source.info = NULL;
arg->source.texture = 0;
arg->source.one_minus = FALSE;
arg->source.mask = statement->mask;
arg->factor.is_one = FALSE;
arg->factor.is_color = FALSE;
arg->factor.is_src_alpha_saturate = FALSE;
arg->factor.source.is_zero = FALSE;
arg->factor.source.info = NULL;
arg->factor.source.texture = 0;
arg->factor.source.one_minus = FALSE;
arg->factor.source.mask = statement->mask;
do
{
if (g_ascii_isspace (*p))
continue;
if (*p == '\0')
{
error_string = "Unexpected end of string while parsing argument";
goto error;
}
switch (state)
{
case PARSER_ARG_STATE_START:
if (*p == '1')
state = PARSER_ARG_STATE_EXPECT_MINUS;
else if (*p == '0')
{
arg->source.is_zero = TRUE;
state = PARSER_ARG_STATE_EXPECT_END;
}
else
{
p--; /* backtrack */
state = PARSER_ARG_STATE_EXPECT_COLOR_SRC_NAME;
}
continue;
case PARSER_ARG_STATE_EXPECT_MINUS:
if (*p != '-')
{
error_string = "expected a '-' following the 1";
goto error;
}
arg->source.one_minus = TRUE;
state = PARSER_ARG_STATE_EXPECT_COLOR_SRC_NAME;
continue;
case PARSER_ARG_STATE_EXPECT_COLOR_SRC_NAME:
if (!is_symbol_char (*p))
{
error_string = "expected a color source name";
goto error;
}
state = PARSER_ARG_STATE_SCRAPING_COLOR_SRC_NAME;
mark = p;
if (parsing_factor)
arg->factor.is_color = TRUE;
/* fall through */
case PARSER_ARG_STATE_SCRAPING_COLOR_SRC_NAME:
if (!is_symbol_char (*p))
{
CoglBlendStringColorSource *source =
parsing_factor ? &arg->factor.source : &arg->source;
source->info = get_color_src_info (mark, p, context);
if (!source->info)
{
error_string = "Unknown color source name";
goto error;
}
if (source->info->type ==
COGL_BLEND_STRING_COLOR_SOURCE_TEXTURE_N)
{
char *endp;
source->texture =
strtoul (&mark[strlen ("TEXTURE_")], &endp, 10);
if (mark == endp)
{
error_string = "invalid texture number given with "
"TEXTURE_N color source";
goto error;
}
p = endp;
}
state = PARSER_ARG_STATE_MAYBE_COLOR_MASK;
}
else
continue;
/* fall through */
case PARSER_ARG_STATE_MAYBE_COLOR_MASK:
if (*p != '[')
{
p--; /* backtrack */
if (!parsing_factor)
state = PARSER_ARG_STATE_MAYBE_MULT;
else
state = PARSER_ARG_STATE_EXPECT_END;
continue;
}
state = PARSER_ARG_STATE_SCRAPING_MASK;
mark = p;
/* fall through */
case PARSER_ARG_STATE_SCRAPING_MASK:
if (*p == ']')
{
size_t len = p - mark;
CoglBlendStringColorSource *source =
parsing_factor ? &arg->factor.source : &arg->source;
if (len == 5 && strncmp (mark, "[RGBA", len) == 0)
{
if (statement->mask != COGL_BLEND_STRING_CHANNEL_MASK_RGBA)
{
error_string = "You can't use an RGBA color mask if the "
"statement hasn't also got an RGBA= mask";
goto error;
}
source->mask = COGL_BLEND_STRING_CHANNEL_MASK_RGBA;
}
else if (len == 4 && strncmp (mark, "[RGB", len) == 0)
source->mask = COGL_BLEND_STRING_CHANNEL_MASK_RGB;
else if (len == 2 && strncmp (mark, "[A", len) == 0)
source->mask = COGL_BLEND_STRING_CHANNEL_MASK_ALPHA;
else
{
error_string = "Expected a channel mask of [RGBA]"
"[RGB] or [A]";
goto error;
}
if (parsing_factor)
state = PARSER_ARG_STATE_EXPECT_CLOSE_PAREN;
else
state = PARSER_ARG_STATE_MAYBE_MULT;
}
continue;
case PARSER_ARG_STATE_EXPECT_OPEN_PAREN:
if (*p != '(')
{
if (is_alphanum_char (*p))
{
p--; /* compensate for implicit brace and ensure this
* char gets considered part of the blend factor */
implicit_factor_brace = TRUE;
}
else
{
error_string = "Expected '(' around blend factor or alpha "
"numeric character for blend factor name";
goto error;
}
}
else
implicit_factor_brace = FALSE;
parsing_factor = TRUE;
state = PARSER_ARG_STATE_EXPECT_FACTOR;
continue;
case PARSER_ARG_STATE_EXPECT_FACTOR:
if (*p == '1')
state = PARSER_ARG_STATE_MAYBE_MINUS;
else if (*p == '0')
{
arg->source.is_zero = TRUE;
state = PARSER_ARG_STATE_EXPECT_CLOSE_PAREN;
}
else
{
state = PARSER_ARG_STATE_MAYBE_SRC_ALPHA_SATURATE;
mark = p;
}
continue;
case PARSER_ARG_STATE_MAYBE_SRC_ALPHA_SATURATE:
if (!is_symbol_char (*p))
{
size_t len = p - mark;
if (len >= strlen ("SRC_ALPHA_SATURATE") &&
strncmp (mark, "SRC_ALPHA_SATURATE", len) == 0)
{
arg->factor.is_src_alpha_saturate = TRUE;
state = PARSER_ARG_STATE_EXPECT_CLOSE_PAREN;
}
else
{
state = PARSER_ARG_STATE_EXPECT_COLOR_SRC_NAME;
p = mark - 1; /* backtrack */
}
}
continue;
case PARSER_ARG_STATE_MAYBE_MINUS:
if (*p == '-')
{
if (implicit_factor_brace)
{
error_string = "Expected ( ) braces around blend factor with "
"a subtraction";
goto error;
}
arg->factor.source.one_minus = TRUE;
state = PARSER_ARG_STATE_EXPECT_COLOR_SRC_NAME;
}
else
{
arg->factor.is_one = TRUE;
state = PARSER_ARG_STATE_EXPECT_CLOSE_PAREN;
}
continue;
case PARSER_ARG_STATE_EXPECT_CLOSE_PAREN:
if (implicit_factor_brace)
{
p--;
state = PARSER_ARG_STATE_EXPECT_END;
continue;
}
if (*p != ')')
{
error_string = "Expected closing parenthesis after blend factor";
goto error;
}
state = PARSER_ARG_STATE_EXPECT_END;
continue;
case PARSER_ARG_STATE_MAYBE_MULT:
if (*p == '*')
{
state = PARSER_ARG_STATE_EXPECT_OPEN_PAREN;
continue;
}
arg->factor.is_one = TRUE;
state = PARSER_ARG_STATE_EXPECT_END;
/* fall through */
case PARSER_ARG_STATE_EXPECT_END:
if (*p != ',' && *p != ')')
{
error_string = "expected , or )";
goto error;
}
*ret_p = p - 1;
return TRUE;
}
}
while (p++);
error:
{
int offset = p - string;
g_set_error (error,
COGL_BLEND_STRING_ERROR,
COGL_BLEND_STRING_ERROR_ARGUMENT_PARSE_ERROR,
"Syntax error for argument %d at offset %d: %s",
current_arg,
offset,
error_string);
if (COGL_DEBUG_ENABLED (COGL_DEBUG_BLEND_STRINGS))
{
g_debug ("Syntax error for argument %d at offset %d: %s",
current_arg, offset, error_string);
}
return FALSE;
}
}
int
_cogl_blend_string_compile (const char *string,
CoglBlendStringContext context,
CoglBlendStringStatement *statements,
GError **error)
{
const char *p = string;
const char *mark = NULL;
const char *error_string;
ParserState state = PARSER_STATE_EXPECT_DEST_CHANNELS;
CoglBlendStringStatement *statement = statements;
int current_statement = 0;
int current_arg = 0;
int remaining_argc = 0;
#if 0
COGL_DEBUG_SET_FLAG (COGL_DEBUG_BLEND_STRINGS);
#endif
if (COGL_DEBUG_ENABLED (COGL_DEBUG_BLEND_STRINGS))
{
COGL_NOTE (BLEND_STRINGS, "Compiling %s string:\n%s\n",
context == COGL_BLEND_STRING_CONTEXT_BLENDING ?
"blend" : "texture combine",
string);
}
do
{
if (g_ascii_isspace (*p))
continue;
if (*p == '\0')
{
switch (state)
{
case PARSER_STATE_EXPECT_DEST_CHANNELS:
if (current_statement != 0)
goto finished;
error_string = "Empty statement";
goto error;
case PARSER_STATE_SCRAPING_DEST_CHANNELS:
error_string = "Expected an '=' following the destination "
"channel mask";
goto error;
case PARSER_STATE_EXPECT_FUNCTION_NAME:
error_string = "Expected a function name";
goto error;
case PARSER_STATE_SCRAPING_FUNCTION_NAME:
error_string = "Expected parenthesis after the function name";
goto error;
case PARSER_STATE_EXPECT_ARG_START:
error_string = "Expected to find the start of an argument";
goto error;
case PARSER_STATE_EXPECT_STATEMENT_END:
error_string = "Expected closing parenthesis for statement";
goto error;
}
}
switch (state)
{
case PARSER_STATE_EXPECT_DEST_CHANNELS:
mark = p;
state = PARSER_STATE_SCRAPING_DEST_CHANNELS;
/* fall through */
case PARSER_STATE_SCRAPING_DEST_CHANNELS:
if (*p != '=')
continue;
if (strncmp (mark, "RGBA", 4) == 0)
statement->mask = COGL_BLEND_STRING_CHANNEL_MASK_RGBA;
else if (strncmp (mark, "RGB", 3) == 0)
statement->mask = COGL_BLEND_STRING_CHANNEL_MASK_RGB;
else if (strncmp (mark, "A", 1) == 0)
statement->mask = COGL_BLEND_STRING_CHANNEL_MASK_ALPHA;
else
{
error_string = "Unknown destination channel mask; "
"expected RGBA=, RGB= or A=";
goto error;
}
state = PARSER_STATE_EXPECT_FUNCTION_NAME;
continue;
case PARSER_STATE_EXPECT_FUNCTION_NAME:
mark = p;
state = PARSER_STATE_SCRAPING_FUNCTION_NAME;
/* fall through */
case PARSER_STATE_SCRAPING_FUNCTION_NAME:
if (*p != '(')
{
if (!is_alphanum_char (*p))
{
error_string = "non alpha numeric character in function"
"name";
goto error;
}
continue;
}
statement->function = get_function_info (mark, p, context);
if (!statement->function)
{
error_string = "Unknown function name";
goto error;
}
remaining_argc = statement->function->argc;
current_arg = 0;
state = PARSER_STATE_EXPECT_ARG_START;
/* fall through */
case PARSER_STATE_EXPECT_ARG_START:
if (*p != '(' && *p != ',')
continue;
if (remaining_argc)
{
p++; /* parse_argument expects to see the first char of the arg */
if (!parse_argument (string, &p, statement,
current_arg, &statement->args[current_arg],
context, error))
return 0;
current_arg++;
remaining_argc--;
}
if (!remaining_argc)
state = PARSER_STATE_EXPECT_STATEMENT_END;
continue;
case PARSER_STATE_EXPECT_STATEMENT_END:
if (*p != ')')
{
error_string = "Expected end of statement";
goto error;
}
state = PARSER_STATE_EXPECT_DEST_CHANNELS;
if (current_statement++ == 1)
goto finished;
statement = &statements[current_statement];
}
}
while (p++);
finished:
if (COGL_DEBUG_ENABLED (COGL_DEBUG_BLEND_STRINGS))
{
if (current_statement > 0)
print_statement (0, &statements[0]);
if (current_statement > 1)
print_statement (1, &statements[1]);
}
if (!validate_statements_for_context (statements,
current_statement,
context,
error))
return 0;
return current_statement;
error:
{
int offset = p - string;
g_set_error (error,
COGL_BLEND_STRING_ERROR,
COGL_BLEND_STRING_ERROR_PARSE_ERROR,
"Syntax error at offset %d: %s",
offset,
error_string);
if (COGL_DEBUG_ENABLED (COGL_DEBUG_BLEND_STRINGS))
{
g_debug ("Syntax error at offset %d: %s",
offset, error_string);
}
return 0;
}
}
/*
* INTERNAL TESTING CODE ...
*/
struct _TestString
{
const char *string;
CoglBlendStringContext context;
};
/* FIXME: this should probably be moved to a unit test */
int
_cogl_blend_string_test (void);
int
_cogl_blend_string_test (void)
{
struct _TestString strings[] = {
{" A = MODULATE ( TEXTURE[RGB], PREVIOUS[A], PREVIOUS[A] ) ",
COGL_BLEND_STRING_CONTEXT_TEXTURE_COMBINE },
{" RGB = MODULATE ( TEXTURE[RGB], PREVIOUS[A] ) ",
COGL_BLEND_STRING_CONTEXT_TEXTURE_COMBINE },
{"A=ADD(TEXTURE[A],PREVIOUS[RGB])",
COGL_BLEND_STRING_CONTEXT_TEXTURE_COMBINE },
{"A=ADD(TEXTURE[A],PREVIOUS[RGB])",
COGL_BLEND_STRING_CONTEXT_TEXTURE_COMBINE },
{"RGBA = ADD(SRC_COLOR*(SRC_COLOR[A]), DST_COLOR*(1-SRC_COLOR[A]))",
COGL_BLEND_STRING_CONTEXT_BLENDING },
{"RGB = ADD(SRC_COLOR, DST_COLOR*(0))",
COGL_BLEND_STRING_CONTEXT_BLENDING },
{"RGB = ADD(SRC_COLOR, 0)",
COGL_BLEND_STRING_CONTEXT_BLENDING },
{"RGB = ADD()",
COGL_BLEND_STRING_CONTEXT_BLENDING },
{"RGB = ADD(SRC_COLOR, 0, DST_COLOR)",
COGL_BLEND_STRING_CONTEXT_BLENDING },
{NULL}
};
int i;
GError *error = NULL;
for (i = 0; strings[i].string; i++)
{
CoglBlendStringStatement statements[2];
int count = _cogl_blend_string_compile (strings[i].string,
strings[i].context,
statements,
&error);
if (!count)
{
g_print ("Failed to parse string:\n%s\n%s\n",
strings[i].string,
error->message);
g_error_free (error);
error = NULL;
continue;
}
g_print ("Original:\n");
g_print ("%s\n", strings[i].string);
if (count > 0)
print_statement (0, &statements[0]);
if (count > 1)
print_statement (1, &statements[1]);
}
return 0;
}
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