rotate_vector.c

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/*****************************************************************************
 * ugBASIC - an isomorphic BASIC language compiler for retrocomputers        *
 *****************************************************************************
 * Copyright 2021-2026 Marco Spedaletti (asimov@mclink.it)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *----------------------------------------------------------------------------
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 * (la "Licenza"); è proibito usare questo file se non in conformità alla
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 * http://www.apache.org/licenses/LICENSE-2.0
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 * Se non richiesto dalla legislazione vigente o concordato per iscritto,
 * il software distribuito nei termini della Licenza è distribuito
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/****************************************************************************
 * INCLUDE SECTION 
 ****************************************************************************/
 
#include "../../ugbc.h"
 
/****************************************************************************
 * CODE SECTION 
 ****************************************************************************/

/* <usermanual>
@keyword ROTATE VECTOR
 
@english 
 
This command allows you to rotate a two-dimensional ''VECTOR'' by a given angle.
 
@italian
 
Questo comando consente di ruotare un vettore bidimensionale (''VECTOR'') di un certo angolo dato.
 
@syntax = ROTATE VECTOR( vector, angle )
 
@example DIM p AS VECTOR
@example    v = CREATE VECTOR( 10, 10 )
@example    v = ROTATE VECTOR( v, 1.57 )
 
</usermanual> */
 
Variable * rotate_vector( Environment * _environment, char * _v, char * _a ) {
 
    deploy_begin( rotate_vector );
 
        Variable * vector = variable_define( _environment, "rotatevector__vector", VT_VECTOR2, 0 );
        Variable * angle = variable_define( _environment, "rotatevector__angle", VT_FLOAT, 0 );
 
        Variable * x = vector_get_x( _environment, vector->name );
        Variable * y = vector_get_y( _environment, vector->name );
 
        Variable * ca = fp_cos( _environment, angle->name );
        Variable * sa = fp_sin( _environment, angle->name );
 
        Variable * xpca = variable_mul( _environment, x->name, ca->name );
        Variable * ypsa = variable_mul( _environment, y->name, sa->name );
        Variable * xpsa = variable_mul( _environment, x->name, sa->name );
        Variable * ypca = variable_mul( _environment, y->name, ca->name );
 
        cpu_move_16bit( _environment, variable_cast( _environment, variable_sub( _environment, xpca->name, ypsa->name)->name, VT_POSITION )->realName, vector->realName );
        cpu_move_16bit( _environment, variable_cast( _environment, variable_add( _environment, xpsa->name, ypca->name)->name, VT_POSITION )->realName, address_displacement( _environment, vector->realName, "2" ) );
 
        cpu_return( _environment );
 
    deploy_end( rotate_vector )
 
    Variable * vp = variable_retrieve( _environment, "rotatevector__vector" );
    Variable * ap = variable_retrieve( _environment, "rotatevector__angle" );
 
    Variable * v = variable_retrieve( _environment, _v );
    Variable * a = variable_retrieve_or_define( _environment, _a, VT_FLOAT, 0 );
 
    variable_move( _environment, v->name, vp->name );
    variable_move( _environment, a->name, ap->name );
 
    cpu_call( _environment, "lib_rotate_vector" );
 
    return vp;
 
}