#ifndef GATE_H
#define GATE_H
+#include "common.h"
+#include "model.h"
+#include "render.h"
+#include "shaders/gate.h"
+#include "shaders/gatelq.h"
+#include "water.h"
+
+typedef struct teleport_gate teleport_gate;
+
+static struct
+{
+ struct framebuffer fb;
+ glmesh mdl;
+
+ int high_qual; /* If in high performance mode, we don't use RT's, and
+ instead use stencil buffers.
+ There is therefore no heat warp effect. */
+}
+grender =
+{
+ .high_qual = 0,
+ .fb = {
+ .format = GL_RGB,
+ .div = 1
+ }
+};
+
+struct teleport_gate
+{
+ v3f co[2];
+ v4f q[2];
+ v2f dims;
+
+ m4x3f to_world, recv_to_world, transport;
+};
+
+static void gate_transform_update( teleport_gate *gate )
+{
+ m4x3f to_local;
+
+ q_m3x3( gate->q[0], gate->to_world );
+ v3_copy( gate->co[0], gate->to_world[3] );
+
+ m4x3_invert_affine( gate->to_world, to_local );
+
+ q_m3x3( gate->q[1], gate->recv_to_world );
+ v3_copy( gate->co[1], gate->recv_to_world[3] );
+ m4x3_mul( gate->recv_to_world, to_local, gate->transport );
+}
+
+static void gate_register(void)
+{
+ shader_gate_register();
+ shader_gatelq_register();
+}
+
+static void gate_init(void)
+{
+ fb_init( &grender.fb );
+
+ mdl_header *mgate = mdl_load( "models/rs_gate.mdl" );
+ mdl_unpack_glmesh( mgate, &grender.mdl );
+ free( mgate );
+}
+
+static void gate_fb_resize(void)
+{
+ fb_resize( &grender.fb );
+}
+
+static int render_gate( teleport_gate *gate, v3f viewpos, m4x3f camera )
+{
+ v3f viewdir, gatedir;
+ m3x3_mulv( camera, (v3f){0.0f,0.0f,-1.0f}, viewdir );
+ m3x3_mulv( gate->to_world, (v3f){0.0f,0.0f,-1.0f}, gatedir );
+
+ v3f v0;
+ v3_sub( viewpos, gate->co[0], v0 );
+ if( v3_dot(v0, gatedir) >= 0.0f )
+ return 0;
+
+ if( v3_dist( viewpos, gate->co[0] ) > 100.0f )
+ return 0;
+
+ v3f a,b,c,d;
+
+ float sx = gate->dims[0],
+ sy = gate->dims[1];
+ m4x3_mulv( gate->to_world, (v3f){-sx,-sy,0.0f}, a );
+ m4x3_mulv( gate->to_world, (v3f){ sx,-sy,0.0f}, b );
+ m4x3_mulv( gate->to_world, (v3f){ sx, sy,0.0f}, c );
+ m4x3_mulv( gate->to_world, (v3f){-sx, sy,0.0f}, d );
+
+ vg_line( a,b, 0xffffa000 );
+ vg_line( b,c, 0xffffa000 );
+ vg_line( c,d, 0xffffa000 );
+ vg_line( d,a, 0xffffa000 );
+
+ vg_line2( gate->co[0], gate->co[1], 0xff0000ff, 0x00000000 );
+
+ m4x3f cam_new;
+ m4x3_mul( gate->transport, camera, cam_new );
+
+ vg_line_pt3( cam_new[3], 0.3f, 0xff00ff00 );
+
+ m4x3f gate_xform;
+ m4x3_copy( gate->to_world, gate_xform );
+ m4x3_scalev( gate_xform, (v3f){ gate->dims[0], gate->dims[1], 1.0f } );
+
+ m4x3f inverse;
+ m4x3_invert_affine( cam_new, inverse );
+
+ m4x4f view;
+ m4x3_expand( inverse, view );
+
+ v4f surface;
+ m3x3_mulv( gate->recv_to_world, (v3f){0.0f,0.0f,-1.0f}, surface );
+ surface[3] = v3_dot( surface, gate->co[1] );
+
+ m4x4f projection;
+ pipeline_projection( projection, 0.1f, 900.0f );
+
+ m4x3_mulp( inverse, surface, surface );
+ surface[3] = -fabsf(surface[3]);
+ plane_clip_projection( projection, surface );
+
+ m4x4_mul( projection, view, projection );
+
+ if( grender.high_qual )
+ {
+ fb_use( &grender.fb );
+ glClearColor( 0.11f, 0.35f, 0.37f, 1.0f );
+ glClear( GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT );
+ }
+ else
+ {
+ shader_gatelq_use();
+ shader_gatelq_uPv( vg_pv );
+ shader_gatelq_uMdl( gate_xform );
+ shader_gatelq_uCam( viewpos );
+ shader_gatelq_uTime( vg_time*0.25f );
+ shader_gatelq_uInvRes( (v2f){
+ 1.0f / (float)vg_window_x,
+ 1.0f / (float)vg_window_y });
+
+ glEnable( GL_STENCIL_TEST );
+ glStencilOp( GL_KEEP, GL_KEEP, GL_REPLACE );
+ glStencilFunc( GL_ALWAYS, 1, 0xFF );
+ glStencilMask( 0xFF );
+
+ mesh_bind( &grender.mdl );
+ mesh_draw( &grender.mdl );
+
+ glClear( GL_DEPTH_BUFFER_BIT );
+ glStencilFunc( GL_EQUAL, 1, 0xFF );
+ glStencilMask( 0x00 );
+ }
+
+ render_world( projection, cam_new );
+
+ if( grender.high_qual )
+ {
+ /*
+ * TODO: Need to find a way to draw a stencil buffer into the water
+ * rendering
+ */
+
+ render_water_texture( cam_new );
+ fb_use( &grender.fb );
+
+ render_water_surface( projection, cam_new );
+ fb_use( NULL );
+
+ shader_gate_use();
+
+ shader_gate_uPv( vg_pv );
+ shader_gate_uMdl( gate_xform );
+
+ fb_bindtex( &grender.fb, 0 );
+
+ shader_gate_uCam( viewpos );
+ shader_gate_uTexMain( 0 );
+ shader_gate_uTexWater( 1 );
+ shader_gate_uTime( vg_time*0.25f );
+ shader_gate_uInvRes( (v2f){
+ 1.0f / (float)vg_window_x,
+ 1.0f / (float)vg_window_y });
+
+ glEnable(GL_BLEND);
+ glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA);
+ glBlendEquation(GL_FUNC_ADD);
+
+ mesh_bind( &grender.mdl );
+ mesh_draw( &grender.mdl );
+
+ glDisable(GL_BLEND);
+ }
+ else
+ {
+ glDisable( GL_STENCIL_TEST );
+
+ render_water_texture( cam_new );
+ fb_use( NULL );
+ glEnable( GL_STENCIL_TEST );
+
+ render_water_surface( projection, cam_new );
+
+ glStencilMask( 0xFF );
+ glStencilFunc( GL_ALWAYS, 1, 0xFF );
+ glDisable( GL_STENCIL_TEST );
+ }
+
+ return 1;
+}
+
+static int gate_intersect( teleport_gate *gate, v3f pos, v3f last )
+{
+ v4f surface;
+ m3x3_mulv( gate->to_world, (v3f){0.0f,0.0f,-1.0f}, surface );
+ surface[3] = v3_dot( surface, gate->co[0] );
+
+ v3f v0, c, delta, p0;
+ v3_sub( pos, last, v0 );
+ float l = v3_length( v0 );
+ v3_divs( v0, l, v0 );
+
+ v3_muls( surface, surface[3], c );
+ v3_sub( c, last, delta );
+
+ float d = v3_dot(surface, v0);
+
+ if( d > 0.00001f )
+ {
+ float t = v3_dot(delta, surface) / d;
+ if( t >= 0.0f && t <= l )
+ {
+ v3f local, rel;
+ v3_muladds( last, v0, t, local );
+ v3_sub( gate->co[0], local, rel );
+
+ v3f vup, vside;
+ m3x3_mulv( gate->to_world, (v3f){0.0f,1.0f,0.0f}, vup );
+ m3x3_mulv( gate->to_world, (v3f){1.0f,0.0f,0.0f}, vside );
+
+ v2f xy = { v3_dot( rel, vside ), v3_dot( rel, vup ) };
+
+ if( fabsf(xy[0]) <= gate->dims[0] && fabsf(xy[1]) <= gate->dims[1] )
+ {
+ return 1;
+ }
+ }
+ }
+
+ return 0;
+}
+
#endif