/*!
Draws a fog plane at the far clipping plane to mask out clipping of terrain.
\return none
\author jfpatry
\date Created: 2000-08-31
\date Modified: 2000-08-31
*/
void draw_fog_plane()
{
plane_t left_edge_plane, right_edge_plane;
plane_t left_clip_plane, right_clip_plane;
plane_t far_clip_plane;
plane_t bottom_clip_plane;
plane_t bottom_plane, top_plane;
scalar_t course_width, course_length;
scalar_t course_angle, slope;
point_t left_pt, right_pt, pt;
point_t top_left_pt, top_right_pt;
point_t bottom_left_pt, bottom_right_pt;
vector_t left_vec, right_vec;
scalar_t height;
GLfloat *fog_colour;
if ( is_fog_on() == False ) {
return;
}
set_gl_options( FOG_PLANE );
get_course_dimensions( &course_width, &course_length );
course_angle = get_course_angle();
slope = tan( ANGLES_TO_RADIANS( course_angle ) );
left_edge_plane = make_plane( 1.0, 0.0, 0.0, 0.0 );
right_edge_plane = make_plane( -1.0, 0.0, 0.0, course_width );
far_clip_plane = get_far_clip_plane();
left_clip_plane = get_left_clip_plane();
right_clip_plane = get_right_clip_plane();
bottom_clip_plane = get_bottom_clip_plane();
/* Find the bottom plane */
bottom_plane.nml = make_vector( 0.0, 1, -slope );
height = get_terrain_base_height( 0 );
/* Unoptimized version
pt = make_point( 0, height, 0 );
bottom_plane.d = -( pt.x * bottom_plane.nml.x +
pt.y * bottom_plane.nml.y +
pt.z * bottom_plane.nml.z );
*/
bottom_plane.d = -height * bottom_plane.nml.y;
/* Find the top plane */
top_plane.nml = bottom_plane.nml;
height = get_terrain_max_height( 0 );
top_plane.d = -height * top_plane.nml.y;
if(get_player_data(local_player())->view.mode == TUXEYE)
{
bottom_clip_plane.nml = make_vector( 0.0, 1, -slope );
height = get_terrain_base_height( 0 ) - 40;
bottom_clip_plane.d = -height * bottom_clip_plane.nml.y;
}
/* Now find the bottom left and right points of the fog plane */
if ( !intersect_planes( bottom_plane, far_clip_plane, left_clip_plane, &left_pt ) )
return;
if ( !intersect_planes( bottom_plane, far_clip_plane, right_clip_plane, &right_pt ) )
return;
if ( !intersect_planes( top_plane, far_clip_plane, left_clip_plane, &top_left_pt ) )
return;
if ( !intersect_planes( top_plane, far_clip_plane, right_clip_plane, &top_right_pt ) )
return;
if ( !intersect_planes( bottom_clip_plane, far_clip_plane, left_clip_plane, &bottom_left_pt ) )
return;
if ( !intersect_planes( bottom_clip_plane, far_clip_plane, right_clip_plane, &bottom_right_pt ) )
return;
left_vec = subtract_points( top_left_pt, left_pt );
right_vec = subtract_points( top_right_pt, right_pt );
/* Now draw the fog plane */
set_gl_options( FOG_PLANE );
fog_colour = get_fog_colour();
glColor4fv( fog_colour );
#ifdef __APPLE__DISABLED__
#undef glEnableClientState
#undef glDisableClientState
#undef glVertexPointer
#undef glColorPointer
#undef glDrawArrays
point_t pt1,pt2,pt3,pt4;
pt1 = move_point( top_left_pt, left_vec );
pt2 = move_point( top_right_pt, right_vec );
pt3 = move_point( top_left_pt, scale_vector( 3.0, left_vec ) );
pt4 = move_point( top_right_pt, scale_vector( 3.0, right_vec ) );
const GLfloat verticesFog []=
{
bottom_left_pt.x, bottom_left_pt.y, bottom_left_pt.z,
bottom_right_pt.x, bottom_right_pt.y, bottom_right_pt.z,
left_pt.x, left_pt.y, left_pt.z,
right_pt.x, right_pt.y, right_pt.z,
top_left_pt.x, top_left_pt.y, top_left_pt.z,
top_right_pt.x, top_right_pt.y, top_right_pt.z,
pt1.x, pt1.y, pt1.z,
pt2.x, pt2.y, pt2.z,
pt3.x, pt3.y, pt3.z,
pt4.x, pt4.y, pt4.z
};
const GLfloat colorsFog []=
{
fog_colour[0], fog_colour[1], fog_colour[2], fog_colour[3],
fog_colour[0], fog_colour[1], fog_colour[2], fog_colour[3],
fog_colour[0], fog_colour[1], fog_colour[2], fog_colour[3],
fog_colour[0], fog_colour[1], fog_colour[2], fog_colour[3],
fog_colour[0], fog_colour[1], fog_colour[2], 0.9 ,
fog_colour[0], fog_colour[1], fog_colour[2], 0.9 ,
fog_colour[0], fog_colour[1], fog_colour[2], 0.3 ,
fog_colour[0], fog_colour[1], fog_colour[2], 0.3 ,
fog_colour[0], fog_colour[1], fog_colour[2], 0.0 ,
fog_colour[0], fog_colour[1], fog_colour[2], 0.0 ,
};
glEnableClientState (GL_VERTEX_ARRAY);
// glEnableClientState (GL_COLOR_ARRAY);
// glDisableClientState(GL_TEXTURE_COORD_ARRAY);
glVertexPointer (3, GL_FLOAT , 0, verticesFog);
glColorPointer(4, GL_FLOAT, 0, colorsFog);
glDrawArrays(GL_TRIANGLE_STRIP, 0, 10);
//glDisableClientState(GL_COLOR_ARRAY_POINTER);
#else
glBegin( GL_QUAD_STRIP );
glVertex3f( bottom_left_pt.x, bottom_left_pt.y, bottom_left_pt.z );
glVertex3f( bottom_right_pt.x, bottom_right_pt.y, bottom_right_pt.z );
glVertex3f( left_pt.x, left_pt.y, left_pt.z );
glVertex3f( right_pt.x, right_pt.y, right_pt.z );
glColor4f( fog_colour[0], fog_colour[1], fog_colour[2], 0.9 );
glVertex3f( top_left_pt.x, top_left_pt.y, top_left_pt.z );
glVertex3f( top_right_pt.x, top_right_pt.y, top_right_pt.z );
glColor4f( fog_colour[0], fog_colour[1], fog_colour[2], 0.3 );
pt = move_point( top_left_pt, left_vec );
glVertex3f( pt.x, pt.y, pt.z );
pt = move_point( top_right_pt, right_vec );
glVertex3f( pt.x, pt.y, pt.z );
glColor4f( fog_colour[0], fog_colour[1], fog_colour[2], 0.0 );
pt = move_point( top_left_pt, scale_vector( 3.0, left_vec ) );
glVertex3f( pt.x, pt.y, pt.z );
pt = move_point( top_right_pt, scale_vector( 3.0, right_vec ) );
glVertex3f( pt.x, pt.y, pt.z );
glEnd();
#endif
}
void quadsquare::Render(const quadcornerdata& cd, GLubyte *vnc_array)
// Draws the heightfield represented by this tree.
// Returns the number of triangles rendered.
{
VNCArray = vnc_array;
bool_t fog_on;
unsigned int i, j;
int nx, ny;
get_course_divisions( &nx, &ny );
/* Save fog state */
fog_on = is_fog_on();
/*
* Draw the "normal" blended triangles ( <= 2 terrains textures )
*/
for (j=0; j<NumTerrains; j++) {
InitArrayCounters();
RenderAux(cd, SomeClip, j);
if ( VertexArrayCounter == 0 ) {
continue;
}
glBindTexture( GL_TEXTURE_2D, TexId[j] );
DrawTris();
if ( j == Ice && getparam_terrain_envmap() ) {
/* Render Ice with environment map */
glDisableClientState( GL_COLOR_ARRAY );
glColor4f( 1.0, 1.0, 1.0, ENV_MAP_ALPHA / 255.0 );
DrawEnvmapTris();
glEnableClientState( GL_COLOR_ARRAY );
}
}
/*
* Draw the "special" triangles that have different terrain types
* at each of the corners
*/
if ( getparam_terrain_blending() &&
getparam_perfect_terrain_blending() ) {
/*
* Get the "special" three-terrain triangles
*/
InitArrayCounters();
RenderAux( cd, SomeClip, -1 );
if ( VertexArrayCounter != 0 ) {
/* Render black triangles */
glDisable( GL_FOG );
/* Set triangle vertices to black */
for (i=0; i<VertexArrayCounter; i++) {
colorval( VertexArrayIndices[i], 0 ) = 0;
colorval( VertexArrayIndices[i], 1 ) = 0;
colorval( VertexArrayIndices[i], 2 ) = 0;
colorval( VertexArrayIndices[i], 3 ) = 255;
}
/* Draw the black triangles */
glBindTexture( GL_TEXTURE_2D, TexId[0] );
DrawTris();
/* Now we draw the triangle once for each texture */
if (fog_on) {
glEnable( GL_FOG );
}
/* Use additive blend function */
glBlendFunc( GL_SRC_ALPHA, GL_ONE );
/* First set triangle colours to white */
for (i=0; i<VertexArrayCounter; i++) {
colorval( VertexArrayIndices[i], 0 ) = 255;
colorval( VertexArrayIndices[i], 1 ) = 255;
colorval( VertexArrayIndices[i], 2 ) = 255;
}
for (j=0; j<NumTerrains; j++) {
glBindTexture( GL_TEXTURE_2D, TexId[j] );
/* Set alpha values */
for (i=0; i<VertexArrayCounter; i++) {
colorval( VertexArrayIndices[i], 3 ) =
(Terrain[VertexArrayIndices[i]] == (terrain_t)j ) ?
255 : 0;
}
DrawTris();
}
/* Render Ice with environment map */
if ( getparam_terrain_envmap() ) {
glBlendFunc( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA );
/* Need to set alpha values for ice */
for (i=0; i<VertexArrayCounter; i++) {
colorval( VertexArrayIndices[i], 3 ) =
(Terrain[VertexArrayIndices[i]] == Ice) ?
ENV_MAP_ALPHA : 0;
}
DrawEnvmapTris();
}
}
}
glBlendFunc( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA );
}
