#pragma once
+#include "vg/vg_engine.h"
+#include "vg/vg_platform.h"
+#include "vg/vg_m.h"
+#include "vg/vg_lines.h"
+#include "vg/vg_async.h"
+#include "vg/vg_camera.h"
#include "trail.h"
+#include "shaders/particle.h"
+#include "shaders/trail.h"
-static void trail_system_update( trail_system *sys, f32 dt,
- v3f co, v3f normal, f32 alpha ){
+static void trail_increment( trail_system *sys ){
+ sys->head ++;
+
+ if( sys->head == sys->max )
+ sys->head = 0;
+
+ /* undesirable effect: will remove active points if out of space! */
+ if( sys->count < sys->max )
+ sys->count ++;
+}
+
+void trail_system_update( trail_system *sys, f32 dt,
+ v3f co, v3f normal, f32 alpha )
+{
/* update existing points and clip dead ones */
bool clip_allowed = 1;
for( i32 i=0; i<sys->count; i ++ ){
}
}
- bool add_point = 1;
- i32 index_current = sys->head;
- if( sys->count >= 2 ) index_current = sys->head -1;
+ i32 icur = sys->head -1,
+ iprev = sys->head -2,
+ ihead = sys->head;
- i32 index_prev = index_current -1;
+ if( icur < 0 ) icur += sys->max;
+ if( iprev < 0 ) iprev += sys->max;
- if( index_current < 0 ) index_current += sys->max;
- if( index_prev < 0 ) index_prev += sys->max;
+ trail_point *pcur = &sys->array[ icur ],
+ *pprev = &sys->array[ iprev ],
+ *phead = &sys->array[ ihead ],
+ *pdest = NULL;
+ v3f dir;
- /* always enforced non-zero distance */
- if( sys->count >= 1 ){
- if( v3_dist2( sys->array[index_prev].co, co ) < 0.001f*0.001f )
- return;
- }
+ f32 k_min = 0.001f;
- /* copy new info in */
- trail_point *p_current = &sys->array[index_current];
- v3_copy( co, p_current->co );
- v3_copy( normal, p_current->normal );
- p_current->alpha = alpha;
-
- /* update direction */
- if( sys->count >= 2 ){
- trail_point *p_prev = &sys->array[index_prev];
-
- v3f dir;
- v3_sub( co, p_prev->co, dir );
- v3_normalize( dir );
- v3_cross( dir, normal, p_current->right );
- v3_copy( p_current->right, p_prev->right );
-
- /* decide if to prevent split based on user min-distance */
- if( v3_dist2( p_prev->co, co ) < sys->min_dist*sys->min_dist )
- add_point = 0;
+ if( sys->count == 0 ){
+ trail_increment( sys );
+ v3_copy( (v3f){0,0,-1}, dir );
+ pdest = phead;
}
- else
- v3_zero( p_current->right );
-
- if( add_point ){
- sys->head ++;
+ else if( sys->count == 1 ){
+ if( v3_dist2( pcur->co, co ) < k_min*k_min )
+ return;
- if( sys->head == sys->max )
- sys->head = 0;
+ trail_increment( sys );
+ pdest = phead;
+ v3_sub( co, pcur->co, dir );
+ }
+ else {
+ if( v3_dist2( pprev->co, co ) < k_min*k_min )
+ return;
- /* undesirable effect: will remove active points if out of space! */
- if( sys->count < sys->max )
- sys->count ++;
+ if( v3_dist2( pprev->co, co ) > sys->min_dist*sys->min_dist ){
+ trail_increment( sys );
+ pdest = phead;
+ }
+ else
+ pdest = pcur;
- index_current = sys->head;
+ v3_sub( co, pprev->co, dir );
}
- p_current = &sys->array[index_current];
- v3_copy( co, p_current->co );
- v3_copy( normal, p_current->normal );
- p_current->alpha = alpha;
- v3_zero( p_current->right );
+ v3_cross( dir, normal, pdest->right );
+ v3_normalize( pdest->right );
+ v3_copy( co, pdest->co );
+ v3_copy( normal, pdest->normal );
+ pdest->alpha = alpha;
}
-static void trail_system_debug( trail_system *sys ){
+void trail_system_debug( trail_system *sys )
+{
for( i32 i=0; i<sys->count; i ++ ){
i32 i0 = sys->head - sys->count + i;
if( i0 < 0 ) i0 += sys->max;
trail_system *sys;
};
-static void async_trail_init( void *payload, u32 size ){
+void async_trail_init( void *payload, u32 size )
+{
struct trail_init_args *args = payload;
trail_system *sys = args->sys;
VG_CHECK_GL_ERR();
}
-static void trail_alloc( trail_system *sys, u32 max ){
+void trail_alloc( trail_system *sys, u32 max )
+{
size_t stride = sizeof(trail_vert);
sys->max = max;
sys->array = vg_linear_alloc( vg_mem.rtmemory, max*sizeof(trail_point) );
vg_async_dispatch( call, async_trail_init );
}
-static void trail_system_prerender( trail_system *sys ){
-#if 0
+void trail_system_prerender( trail_system *sys )
+{
+ if( sys->count < 2 ) return;
+
+ for( i32 i=0; i<sys->count; i ++ ){
+ i32 i0 = sys->head - sys->count + i;
+ if( i0 < 0 ) i0 += sys->max;
+
+ trail_point *p0 = &sys->array[i0];
+ trail_vert *v0 = &sys->vertices[i*2+0],
+ *v1 = &sys->vertices[i*2+1];
+
+ v3_muladds( p0->co, p0->right, -sys->width, v0->co );
+ v3_muladds( p0->co, p0->right, sys->width, v1->co );
+ v0->co[3] = p0->alpha;
+ v1->co[3] = p0->alpha;
+ }
+
glBindVertexArray( sys->vao );
size_t stride = sizeof(trail_vert);
glBindBuffer( GL_ARRAY_BUFFER, sys->vbo );
- glBufferSubData( GL_ARRAY_BUFFER, 0, sys->alive*stride*4, sys->vertices );
-#endif
+ glBufferSubData( GL_ARRAY_BUFFER, 0, sys->count*stride*2, sys->vertices );
}
-static void trail_system_render( trail_system *sys, camera *cam ){
-#if 0
+void trail_system_render( trail_system *sys, vg_camera *cam )
+{
+ if( sys->count < 2 ) return;
glDisable( GL_CULL_FACE );
glEnable( GL_DEPTH_TEST );
shader_trail_use();
shader_trail_uPv( cam->mtx.pv );
shader_trail_uPvPrev( cam->mtx_prev.pv );
+ shader_trail_uColour( (v4f){1.0f,1.0f,1.0f,1.0f} );
glBindVertexArray( sys->vao );
- glDrawElements( GL_TRIANGLES, sys->alive*6, GL_UNSIGNED_SHORT, NULL );
-#endif
+ glDrawArrays( GL_TRIANGLE_STRIP, 0, sys->count*2 );
}