#endif
#include <osg/AlphaFunc>
+#include <osg/Depth>
#include <osg/Program>
#include <osg/Uniform>
#include <osg/ref_ptr>
using namespace osg;
typedef std::map<std::string, osg::ref_ptr<osg::StateSet> > StateSetMap;
-typedef std::vector< osg::ref_ptr<osg::Geode> > GeodeList;
-typedef std::map<std::string, GeodeList*> CloudMap;
StateSetMap cloudTextureMap;
-static CloudMap cloudMap;
double SGNewCloud::sprite_density = 1.0;
-unsigned int SGNewCloud::num_flavours = 10;
static char vertexShaderSource[] =
"#version 120\n"
" vec4 backlight = 0.9 * gl_LightSource[0].ambient + 0.1 * gl_LightSource[0].diffuse;\n"
" gl_FrontColor = mix(backlight, gl_LightSource[0].diffuse, n);\n"
" gl_FrontColor += gl_FrontLightModelProduct.sceneColor;\n"
-// As we get within 100m of the sprite, it is faded out
- " gl_FrontColor.a = smoothstep(10.0, 100.0, fogCoord);\n"
+// As we get within 100m of the sprite, it is faded out. Equally at large distances it also fades out.
+ " gl_FrontColor.a = min(smoothstep(10.0, 100.0, fogCoord), 1 - smoothstep(15000.0, 20000.0, fogCoord));\n"
" gl_BackColor = gl_FrontColor;\n"
// Fog doesn't affect clouds as much as other objects.
" fogFactor = exp( -gl_Fog.density * fogCoord * 0.5);\n"
stateSet->setTextureAttributeAndModes(0, tex, osg::StateAttribute::ON );
stateSet->setRenderBinDetails(osg::StateSet::TRANSPARENT_BIN, "DepthSortedBin");
-
+ // Turn off z buffer writes. Standard hack for
+ // semi-transparent geometry to avoid sorting / flickering
+ // artifacts.
+ stateSet->setAttributeAndModes(attribFactory->getDepthWritesDisabled());
static ref_ptr<AlphaFunc> alphaFunc;
static ref_ptr<Program> program;
static ref_ptr<Uniform> baseTextureSampler;
// Generate the shader etc, if we don't already have one.
if (!program.valid()) {
alphaFunc = new AlphaFunc;
- alphaFunc->setFunction(AlphaFunc::GREATER,0.001f);
+ alphaFunc->setFunction(AlphaFunc::GREATER,0.05f);
program = new Program;
baseTextureSampler = new osg::Uniform("baseTexture", 0);
Shader* vertex_shader = new Shader(Shader::VERTEX, vertexShaderSource);
osg::ref_ptr<Geode> SGNewCloud::genCloud() {
- CloudMap::iterator iter = cloudMap.find(name);
- osg::ref_ptr<osg::Geode> geode;
+ osg::ref_ptr<osg::Geode> geode = new Geode;
+
+ CloudShaderGeometry* sg = new CloudShaderGeometry(num_textures_x, num_textures_y, max_width, max_height);
+
+ // Determine how big this specific cloud instance is. Note that we subtract
+ // the sprite size because the width/height is used to define the limits of
+ // the center of the sprites, not their edges.
+ float width = min_width + sg_random() * (max_width - min_width) - min_sprite_width;
+ float height = min_height + sg_random() * (max_height - min_height) - min_sprite_height;
- // We generate up to num_flavours of different versions
- // of the same cloud before we start re-using them. This
- // allows us to strike a balance between performance and
- // visual complexity.
+ // Determine the cull distance. This is used to remove sprites that are too close together.
+ // The value is squared as we use vector calculations.
+ float cull_distance_squared = min_sprite_height * min_sprite_height * 0.1f;
- if (iter == cloudMap.end() || (*iter).second->size() < num_flavours)
+ // The number of sprites we actually used is a function of the (user-controlled) density
+ int n_sprites = num_sprites * sprite_density;
+
+ for (int i = 0; i < n_sprites; i++)
{
+ // Determine the position of the sprite. Rather than being completely random,
+ // we place them on the surface of a distorted sphere. However, we place
+ // the first and second sprites on the top and bottom, and the third in the
+ // center of the sphere (and at maximum size) to ensure good coverage and
+ // reduce the chance of there being "holes" in our cloud.
+ float x, y, z;
- geode = new Geode;
-
- CloudShaderGeometry* sg = new CloudShaderGeometry(num_textures_x, num_textures_y, max_width, max_height);
-
- // Determine how big this specific cloud instance is. Note that we subtract
- // the sprite size because the width/height is used to define the limits of
- // the center of the sprites, not their edges.
- float width = min_width + sg_random() * (max_width - min_width) - min_sprite_width;
- float height = min_height + sg_random() * (max_height - min_height) - min_sprite_height;
-
- // Determine the cull distance. This is used to remove sprites that are too close together.
- // The value is squared as we use vector calculations.
- float cull_distance_squared = min_sprite_height * min_sprite_height * 0.1f;
-
- // The number of sprites we actually used is a function of the (user-controlled) density
- int n_sprites = num_sprites * sprite_density;
-
- for (int i = 0; i < n_sprites; i++)
- {
- // Determine the position of the sprite. Rather than being completely random,
- // we place them on the surface of a distorted sphere. However, we place
- // the first and second sprites on the top and bottom, and the third in the
- // center of the sphere (and at maximum size) to ensure good coverage and
- // reduce the chance of there being "holes" in our cloud.
- float x, y, z;
-
- if (i == 0) {
- x = 0;
- y = 0;
- z = height * 0.5f;
- } else if (i == 1) {
- x = 0;
- y = 0;
- z = - height * 0.5f;
- } else if (i == 2) {
- x = 0;
- y = 0;
- z = 0;
- } else {
- double theta = sg_random() * SGD_2PI;
- double elev = sg_random() * SGD_PI;
- x = width * cos(theta) * 0.5f * sin(elev);
- y = width * sin(theta) * 0.5f * sin(elev);
- z = height * cos(elev) * 0.5f;
- }
-
- SGVec3f *pos = new SGVec3f(x, y, z);
-
- // Determine the height and width as scaling factors on the minimum size (used to create the quad)
- float sprite_width = 1.0f + sg_random() * (max_sprite_width - min_sprite_width) / min_sprite_width;
- float sprite_height = 1.0f + sg_random() * (max_sprite_height - min_sprite_height) / min_sprite_height;
-
- if (i == 2) {
- // The center sprite is always maximum size to fill up any holes.
- sprite_width = 1.0f + (max_sprite_width - min_sprite_width) / min_sprite_width;
- sprite_height = 1.0f + (max_sprite_height - min_sprite_height) / min_sprite_height;
- }
-
- // Determine the sprite texture indexes;
- int index_x = (int) floor(sg_random() * num_textures_x);
- if (index_x == num_textures_x) { index_x--; }
-
- int index_y = (int) floor(sg_random() * num_textures_y);
- if (index_y == num_textures_y) { index_y--; }
-
- sg->addSprite(*pos,
- index_x,
- index_y,
- sprite_width,
- sprite_height,
- bottom_shade,
- cull_distance_squared,
- height * 0.5f);
+ if (i == 0) {
+ x = 0;
+ y = 0;
+ z = height * 0.5f;
+ } else if (i == 1) {
+ x = 0;
+ y = 0;
+ z = - height * 0.5f;
+ } else if (i == 2) {
+ x = 0;
+ y = 0;
+ z = 0;
+ } else {
+ double theta = sg_random() * SGD_2PI;
+ double elev = sg_random() * SGD_PI;
+ x = width * cos(theta) * 0.5f * sin(elev);
+ y = width * sin(theta) * 0.5f * sin(elev);
+ z = height * cos(elev) * 0.5f;
}
+ SGVec3f *pos = new SGVec3f(x, y, z);
+
+ // Determine the height and width as scaling factors on the minimum size (used to create the quad)
+ float sprite_width = 1.0f + sg_random() * (max_sprite_width - min_sprite_width) / min_sprite_width;
+ float sprite_height = 1.0f + sg_random() * (max_sprite_height - min_sprite_height) / min_sprite_height;
- sg->setGeometry(quad);
- geode->addDrawable(sg);
- geode->setName("3D cloud");
- geode->setStateSet(stateSet.get());
-
- if (iter == cloudMap.end())
- {
- // This is the first of this cloud to be generated.
- GeodeList* geodelist = new GeodeList;
- geodelist->push_back(geode);
- cloudMap.insert(CloudMap::value_type(name, geodelist));
+ if (i == 2) {
+ // The center sprite is always maximum size to fill up any holes.
+ sprite_width = 1.0f + (max_sprite_width - min_sprite_width) / min_sprite_width;
+ sprite_height = 1.0f + (max_sprite_height - min_sprite_height) / min_sprite_height;
}
- else
- {
- // Add the new cloud to the list of geodes
- (*iter).second->push_back(geode);
- }
-
- } else {
- int index = sg_random() * num_flavours;
- if (index == num_flavours) index--;
+ // Determine the sprite texture indexes;
+ int index_x = (int) floor(sg_random() * num_textures_x);
+ if (index_x == num_textures_x) { index_x--; }
- geode = iter->second->at(index);
+ int index_y = (int) floor(sg_random() * num_textures_y);
+ if (index_y == num_textures_y) { index_y--; }
+
+ sg->addSprite(*pos,
+ index_x,
+ index_y,
+ sprite_width,
+ sprite_height,
+ bottom_shade,
+ cull_distance_squared,
+ height * 0.5f);
}
+ sg->setGeometry(quad);
+ geode->addDrawable(sg);
+ geode->setName("3D cloud");
+ geode->setStateSet(stateSet.get());
+
return geode;
}
projects / simgear.git / blobdiff