/**

 * MojoShader; generate shader programs from bytecode of compiled

 *  Direct3D shaders.

 *

 * Please see the file LICENSE.txt in the source's root directory.

 *

 *  This file written by Ryan C. Gordon.

 */

#ifndef __INCL_MOJOSHADER_H_

#define __INCL_MOJOSHADER_H_

#ifdef __cplusplus

extern "C" {

#endif

/*

 * For determining the version of MojoShader you are using:

 *    const int compiled_against = MOJOSHADER_VERSION;

 *    const int linked_against = MOJOSHADER_version();

 *

 * The version is a single integer that increments, not a major/minor value.

 */

#define MOJOSHADER_VERSION 1

int MOJOSHADER_version(void);

/*

 * These allocators work just like the C runtime's malloc() and free()

 *  (in fact, they probably use malloc() and free() internally if you don't

 *  specify your own allocator, but don't rely on that behaviour).

 */

/*

 * These are enum values, but they also can be used in bitmasks, so we can

 *  test if an opcode is acceptable: if (op->shader_types & ourtype) {} ...

 */

typedef enum

{

    MOJOSHADER_TYPE_UNKNOWN  = 0,

    MOJOSHADER_TYPE_PIXEL    = (1 << 0),

    MOJOSHADER_TYPE_VERTEX   = (1 << 1),

    MOJOSHADER_TYPE_GEOMETRY = (1 << 2),  /* (not supported yet.) */

    MOJOSHADER_TYPE_ANY = 0xFFFFFFFF   /* used for bitmasks */

} MOJOSHADER_shaderType;

/*

 * Data types for uniforms. See MOJOSHADER_uniform for more information.

 */

typedef enum

{

    MOJOSHADER_UNIFORM_FLOAT,

    MOJOSHADER_UNIFORM_INT,

    MOJOSHADER_UNIFORM_BOOL

} MOJOSHADER_uniformType;

/*

 * These are the uniforms to be set for a shader. "Uniforms" are what Direct3D

 *  calls "Constants" ... IDirect3DDevice::SetVertexShaderConstantF() would

 *  need this data, for example. These integers are register indexes. So if

 *  index==6 and type==MOJOSHADER_UNIFORM_FLOAT, that means we'd expect a

 *  4-float vector to be specified for what would be register "c6" in D3D

 *  assembly language, before drawing with the shader.

 */

typedef struct

{

    int index;

    MOJOSHADER_uniformType type;

} MOJOSHADER_uniform;

/*

 * Structure used to return data from parsing of a shader...

 */

typedef struct

{

    /*

     * Human-readable error, if there is one. Will be NULL if there was no

     *  error. The string will be UTF-8 encoded, and English only. Most of

     *  these shouldn't be shown to the end-user anyhow.

     */

    const char *error;

    /*

     * Bytes of output from parsing. Most profiles produce a string of source

     *  code, but profiles that do binary output may not be text at all.

     *  Will be NULL on error.

     */

    const char *output;

    /*

     * Byte count for output, not counting any null terminator. Most profiles

     *  produce an ASCII string of source code, but profiles that do binary

     *  output may not be text at all. Will be 0 on error.

     */

    int output_len;

    /*

     * Count of Direct3D instructions we parsed. This is meaningless in terms

     *  of the actual output, as the profile will probably grow or reduce

     *  the count (or for high-level languages, not have that information at

     *  all), but it can give you a rough idea of the size of your shader.

     *  Will be zero on error.

     */

    int instruction_count;

    /*

     * The type of shader we parsed. Will be MOJOSHADER_TYPE_UNKNOWN on error.

     */

    MOJOSHADER_shaderType shader_type;

    /*

     * The shader's major version. If this was a "vs_3_0", this would be 3.

     */

    int major_ver;

    /*

     * The shader's minor version. If this was a "ps_1_4", this would be 4.

     *  Two notes: for "vs_2_x", this is 1, and for "vs_3_sw", this is 255.

     */

    int minor_ver;

    /*

     * The number of elements pointed to by (uniforms).

     */

    int uniform_count;

    /*

     * (uniform_count) elements of data that specify Uniforms to be set for

     *  this shader. See discussion on MOJOSHADER_uniform for details.

     */

    MOJOSHADER_uniform *uniforms;

    /*

     * This is the malloc implementation you passed to MOJOSHADER_parse().

     */

    MOJOSHADER_malloc malloc;

    /*

     * This is the free implementation you passed to MOJOSHADER_parse().

     */

    MOJOSHADER_free free;

} MOJOSHADER_parseData;

/*

 * Profile string for Direct3D assembly language output.

 */

#define MOJOSHADER_PROFILE_D3D "d3d"

/*

 * Profile string for GLSL: OpenGL high-level shader language output.

 */

#define MOJOSHADER_PROFILE_GLSL "glsl"

/*

 * Parse a compiled Direct3D shader's bytecode.

 *

 * This is your primary entry point into MojoShader. You need to pass it

 *  a compiled D3D shader and tell it which "profile" you want to use to

 *  convert it into useful data.

 *

 * The available profiles are the set of MOJOSHADER_PROFILE_* defines.

 *  Note that MojoShader may be built without support for all listed

 *  profiles (in which case using one here will return with an error).

 *

 * As parsing requires some memory to be allocated, you may provide a custom

 *  allocator to this function, which will be used to allocate/free memory.

 *  They function just like malloc() and free(). We do not use realloc().

 *

 *

 * This function will never return NULL, even if the system is completely

 *  out of memory upon entry (in which case, this function returns a static

 *  MOJOSHADER_parseData object, which is still safe to pass to

 *  MOJOSHADER_freeParseData()).

 *

 * This function is thread safe, so long (m) and (f) are too, and that

 *  (tokenbuf) remains intact for the duration of the call. This allows you

 *  to parse several shaders on separate CPU cores at the same time.

 */

const MOJOSHADER_parseData *MOJOSHADER_parse(const char *profile,

                                             const unsigned char *tokenbuf,

                                             const unsigned int bufsize,

                                             MOJOSHADER_malloc m,

/*

 * Call this to dispose of parsing results when you are done with them.

 *  This will call the MOJOSHADER_free function you provided to

 *  MOJOSHADER_parse multiple times, if you provided one.

 *  Passing a NULL here is a safe no-op.

 *

 * This function is thread safe, so long as any allocator you passed into

 *  MOJOSHADER_parse() is, too.

 */

void MOJOSHADER_freeParseData(const MOJOSHADER_parseData *data);

#ifdef __cplusplus

}

#endif

#endif  /* include-once blocker. */

/* end of mojoshader.h ... */