1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/pvr2/gl_sl.c	Tue Mar 11 08:50:16 2008 +0000
     1.3 @@ -0,0 +1,223 @@
     1.4 +/**
     1.5 + * $Id$
     1.6 + *
     1.7 + * GLSL shader loader/unloader. Current version assumes there's exactly
     1.8 + * 1 shader program that's used globally. This may turn out not to be the
     1.9 + * most efficient approach.
    1.10 + *
    1.11 + * Copyright (c) 2007 Nathan Keynes.
    1.12 + *
    1.13 + * This program is free software; you can redistribute it and/or modify
    1.14 + * it under the terms of the GNU General Public License as published by
    1.15 + * the Free Software Foundation; either version 2 of the License, or
    1.16 + * (at your option) any later version.
    1.17 + *
    1.18 + * This program is distributed in the hope that it will be useful,
    1.19 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
    1.20 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    1.21 + * GNU General Public License for more details.
    1.22 + */
    1.23 +
    1.24 +#define GL_GLEXT_PROTOTYPES 1
    1.25 +
    1.26 +#include "lxdream.h"
    1.27 +#include "display.h"
    1.28 +#include "pvr2/glutil.h"
    1.29 +
    1.30 +#define MAX_ERROR_BUF 4096
    1.31 +
    1.32 +gboolean glsl_is_supported()
    1.33 +{
    1.34 +    return isGLExtensionSupported("GL_ARB_fragment_shader") &&
    1.35 +	isGLExtensionSupported("GL_ARB_vertex_shader") &&
    1.36 +	isGLExtensionSupported("GL_ARB_shading_language_100");
    1.37 +}
    1.38 +
    1.39 +#ifdef GL_ARB_shader_objects
    1.40 +static GLhandleARB glsl_program = 0, glsl_vert_shader = 0, glsl_frag_shader = 0;
    1.41 +
    1.42 +void glsl_print_error( char *msg, GLhandleARB obj )
    1.43 +{
    1.44 +    char buf[MAX_ERROR_BUF];
    1.45 +    GLsizei length;
    1.46 +    glGetInfoLogARB( obj, sizeof(buf), &length, buf );
    1.47 +    ERROR( "%s: %s", msg, buf );
    1.48 +}
    1.49 +
    1.50 +gboolean glsl_check_shader_error( char *msg, GLhandleARB obj )
    1.51 +{
    1.52 +    GLint value;
    1.53 +
    1.54 +    glGetObjectParameterivARB(obj, GL_OBJECT_COMPILE_STATUS_ARB, &value);
    1.55 +    if( value == 0 ) {
    1.56 +	glsl_print_error(msg, obj);
    1.57 +	return FALSE;
    1.58 +    }
    1.59 +    return TRUE;
    1.60 +}
    1.61 +
    1.62 +gboolean glsl_check_program_error( char *msg, GLhandleARB obj )
    1.63 +{
    1.64 +    if( glGetError() != GL_NO_ERROR ) {
    1.65 +	glsl_print_error(msg, obj);
    1.66 +    }
    1.67 +    return TRUE;
    1.68 +}
    1.69 +
    1.70 +
    1.71 +gboolean glsl_load_shaders( const char *vertex_src, const char *fragment_src )
    1.72 +{
    1.73 +    gboolean vsok = TRUE, fsok = TRUE, pok = FALSE;
    1.74 +
    1.75 +    if( vertex_src == NULL && fragment_src == NULL ) {
    1.76 +	return TRUE; // nothing to do
    1.77 +    }
    1.78 +
    1.79 +    glsl_program = glCreateProgramObjectARB();
    1.80 +
    1.81 +    if( vertex_src != NULL ) {
    1.82 +	glsl_vert_shader = glCreateShaderObjectARB(GL_VERTEX_SHADER_ARB);
    1.83 +	glShaderSourceARB( glsl_vert_shader, 1, &vertex_src, NULL );
    1.84 +	glCompileShaderARB(glsl_vert_shader);
    1.85 +	vsok = glsl_check_shader_error("Failed to compile vertex shader", glsl_vert_shader);
    1.86 +    }
    1.87 +    if( fragment_src != NULL ) {
    1.88 +	glsl_frag_shader = glCreateShaderObjectARB(GL_FRAGMENT_SHADER_ARB);
    1.89 +	glShaderSourceARB( glsl_frag_shader, 1, &fragment_src, NULL );
    1.90 +	glCompileShaderARB(glsl_frag_shader);
    1.91 +	fsok = glsl_check_shader_error("Failed to compile fragment shader", glsl_frag_shader);
    1.92 +    }
    1.93 +
    1.94 +    if( vsok && fsok ) {
    1.95 +	if( vertex_src != NULL ) {
    1.96 +	    glAttachObjectARB(glsl_program, glsl_vert_shader);
    1.97 +	}
    1.98 +	if( fragment_src != NULL ) {
    1.99 +	    glAttachObjectARB(glsl_program, glsl_frag_shader);
   1.100 +	}
   1.101 +	glLinkProgramARB(glsl_program);
   1.102 +	pok = glsl_check_program_error( "Failed to link shader program", glsl_program );
   1.103 +    }
   1.104 +    if( pok ) {
   1.105 +	glUseProgramObjectARB(glsl_program);
   1.106 +	pok = glsl_check_program_error( "Failed to apply shader program", glsl_program );
   1.107 +    } else {
   1.108 +	glsl_unload_shaders();
   1.109 +    }
   1.110 +    return pok;
   1.111 +}
   1.112 +
   1.113 +void glsl_enable_shader(gboolean en)
   1.114 +{
   1.115 +    if( glsl_program != 0 ) {
   1.116 +	if( en ) {
   1.117 +	    glUseProgramObjectARB(glsl_program);
   1.118 +	} else {
   1.119 +	    glUseProgramObjectARB(0);
   1.120 +	}
   1.121 +    }
   1.122 +}
   1.123 +
   1.124 +void glsl_unload_shaders(void)
   1.125 +{
   1.126 +    glUseProgramObjectARB(0);
   1.127 +    glDetachObjectARB(glsl_program, glsl_vert_shader);
   1.128 +    glDetachObjectARB(glsl_program, glsl_frag_shader);
   1.129 +    glDeleteObjectARB(glsl_program);
   1.130 +    glDeleteObjectARB(glsl_vert_shader);
   1.131 +    glDeleteObjectARB(glsl_frag_shader);
   1.132 +}
   1.133 +
   1.134 +#else
   1.135 +static GLuint glsl_program = 0, glsl_vert_shader = 0, glsl_frag_shader = 0;
   1.136 +
   1.137 +gboolean glsl_check_shader_error( char *msg, GLuint shader )
   1.138 +{
   1.139 +    GLint value;
   1.140 +
   1.141 +    glGetShaderiv( shader, GL_COMPILE_STATUS, &value );
   1.142 +    if( value == 0 ) {
   1.143 +	char buf[MAX_ERROR_BUF];
   1.144 +	GLsizei length;
   1.145 +	glGetShaderInfoLog( shader, sizeof(buf), &length, buf );
   1.146 +	ERROR( "%s: %s", msg, buf );
   1.147 +	return FALSE;
   1.148 +    }
   1.149 +    return TRUE;
   1.150 +}
   1.151 +gboolean glsl_check_program_error( char *msg, GLuint program )
   1.152 +{
   1.153 +    if( glGetError() != GL_NO_ERROR ) {
   1.154 +	char buf[MAX_ERROR_BUF];
   1.155 +	GLsizei length;
   1.156 +	glGetProgramInfoLog( program, sizeof(buf), &length, buf );
   1.157 +	ERROR( "%s: %s", msg, buf );
   1.158 +	return FALSE;
   1.159 +    }
   1.160 +    return TRUE;
   1.161 +}
   1.162 +
   1.163 +gboolean glsl_load_shaders( const char *vertex_src, const char *fragment_src )
   1.164 +{
   1.165 +    gboolean vsok = TRUE, fsok = TRUE, pok = FALSE;
   1.166 +
   1.167 +    if( vertex_src == NULL && fragment_src == NULL ) {
   1.168 +	return TRUE;
   1.169 +    }
   1.170 +
   1.171 +    glsl_program = glCreateProgram();
   1.172 +
   1.173 +    if( vertex_src != NULL ) {
   1.174 +	glsl_vert_shader = glCreateShader(GL_VERTEX_SHADER);
   1.175 +	glShaderSource( glsl_vert_shader, 1, &vertex_src, NULL );
   1.176 +	glCompileShader(glsl_vert_shader);
   1.177 +	vsok = glsl_check_shader_error( "Failed to compile vertex shader", glsl_vert_shader );
   1.178 +    }
   1.179 +    if( fragment_src != NULL ) {
   1.180 +	glsl_frag_shader = glCreateShader(GL_FRAGMENT_SHADER);
   1.181 +	glShaderSource( glsl_frag_shader, 1, &fragment_src, NULL );
   1.182 +	glCompileShader(glsl_frag_shader);
   1.183 +	fsok = glsl_check_shader_error( "Failed to compile fragment shader", glsl_frag_shader );
   1.184 +    }
   1.185 +
   1.186 +    if( vsok && fsok ) {
   1.187 +	if( vertex_src != NULL ) {
   1.188 +	    glAttachShader(glsl_program, glsl_vert_shader);
   1.189 +	}
   1.190 +	if( fragment_src != NULL ) {
   1.191 +	    glAttachShader(glsl_program, glsl_frag_shader);
   1.192 +	}
   1.193 +	glLinkProgram(glsl_program);
   1.194 +	pok = glsl_check_program_error( "Failed to link shader program", glsl_program );
   1.195 +    }
   1.196 +
   1.197 +    if( pok ) {
   1.198 +	glUseProgram(glsl_program);
   1.199 +    } else {
   1.200 +	glsl_unload_shaders();
   1.201 +    }
   1.202 +    return pok;
   1.203 +}
   1.204 +
   1.205 +
   1.206 +void glsl_enable_shader(gboolean en)
   1.207 +{
   1.208 +    if( glsl_program != 0 ) {
   1.209 +	if( en ) {
   1.210 +	    glUseProgram(glsl_program);
   1.211 +	} else {
   1.212 +	    glUseProgram(0);
   1.213 +	}
   1.214 +    }
   1.215 +}
   1.216 +
   1.217 +void glsl_unload_shaders(void)
   1.218 +{
   1.219 +    glUseProgram(0);
   1.220 +    glDetachShader(glsl_program, glsl_vert_shader);
   1.221 +    glDetachShader(glsl_program, glsl_frag_shader);
   1.222 +    glDeleteProgram(glsl_program);
   1.223 +    glDeleteShader(glsl_vert_shader);
   1.224 +    glDeleteShader(glsl_frag_shader);
   1.225 +}
   1.226 +#endif