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Do not render cloudlets on the back half of the cloud at ranges

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of > 10km.  50% performance improvements seen under overcast conditions.
This commit is contained in:
Stuart Buchanan 2012-12-16 22:20:23 +00:00
parent 024f7494e4
commit 4c4df3401e
4 changed files with 209 additions and 182 deletions
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63
Effects/cloud.eff
View file

@ -5,13 +5,15 @@
<texture n ="0">
</texture>
<range><use>/sim/rendering/clouds3d-vis-range</use></range>
<detail><use>/sim/rendering/clouds3d-detail-range</use></detail>
<scattering><use>/rendering/scene/scattering</use></scattering>
<terminator><use>/environment/terminator-relative-position-m</use></terminator>
<altitude><use>/sim/rendering/eye-altitude-m</use></altitude>
<cloud_self_shading><use>/environment/cloud-self-shading</use></cloud_self_shading>
<moonlight><use>/environment/moonlight</use></moonlight>
</parameters>
<technique n="9">
<technique n="9">
<predicate>
<and>
<property>/sim/rendering/shaders/skydome</property>
@ -74,34 +76,40 @@
<type>float</type>
<value><use>range</use></value>
</uniform>
<uniform>
<name>detail_range</name>
<type>float</type>
<value><use>detail</use></value>
</uniform>
<uniform>
<name>scattering</name>
<type>float</type>
<value><use>scattering</use></value>
</uniform>
<uniform>
<name>terminator</name>
<type>float</type>
<value><use>terminator</use></value>
<uniform>
<name>terminator</name>
<type>float</type>
<value><use>terminator</use></value>
</uniform>
<uniform>
<name>altitude</name>
<type>float</type>
<value><use>altitude</use></value>
<uniform>
<name>altitude</name>
<type>float</type>
<value><use>altitude</use></value>
</uniform>
<uniform>
<name>cloud_self_shading</name>
<type>float</type>
<value><use>cloud_self_shading</use></value>
<uniform>
<name>cloud_self_shading</name>
<type>float</type>
<value><use>cloud_self_shading</use></value>
</uniform>
<uniform>
<name>moonlight</name>
<type>float</type>
<value><use>moonlight</use></value>
<uniform>
<name>moonlight</name>
<type>float</type>
<value><use>moonlight</use></value>
</uniform>
<!--<vertex-program-two-side>true</vertex-program-two-side>-->
</pass>
</technique>
<technique n="10">
<predicate>
<less-equal>
@ -162,20 +170,25 @@
<type>float</type>
<value><use>range</use></value>
</uniform>
<uniform>
<name>detail_range</name>
<type>float</type>
<value><use>detail</use></value>
</uniform>
<uniform>
<name>scattering</name>
<type>float</type>
<value><use>scattering</use></value>
</uniform>
<uniform>
<name>terminator</name>
<type>float</type>
<value><use>terminator</use></value>
<uniform>
<name>terminator</name>
<type>float</type>
<value><use>terminator</use></value>
</uniform>
<uniform>
<name>altitude</name>
<type>float</type>
<value><use>altitude</use></value>
<uniform>
<name>altitude</name>
<type>float</type>
<value><use>altitude</use></value>
</uniform>
<vertex-program-two-side>true</vertex-program-two-side>
</pass>

247
Shaders/3dcloud-lightfield.vert
View file

@ -5,6 +5,7 @@ varying float fogFactor;
varying vec3 hazeColor;
uniform float range; // From /sim/rendering/clouds3d-vis-range
uniform float detail_range; // From /sim/rendering/clouds3d_detail-range
uniform float scattering;
uniform float terminator;
uniform float altitude;
@ -88,144 +89,150 @@ void main(void)
normalize(vec3(gl_ModelViewMatrix * vec4(- gl_Position.x, - gl_Position.y, - gl_Position.z, 0.0))));
// Determine the position - used for fog and shading calculations
vec3 ecPosition = vec3(gl_ModelViewMatrix * gl_Position);
float fogCoord = abs(ecPosition.z);
float fogCoord = length(vec3(gl_ModelViewMatrix * vec4(gl_Color.x, gl_Color.y, gl_Color.z, 1.0)));
float center_dist = length(vec3(gl_ModelViewMatrix * vec4(0.0,0.0,0.0,1.0)));
// Determine the shading of the vertex. We shade it based on it's position
// in the cloud relative to the sun, and it's vertical position in the cloud.
float shade = mix(shade_factor, top_factor, smoothstep(-0.3, 0.3, n));
//if (n < 0) {
// shade = mix(top_factor, shade_factor, abs(n));
//}
if (gl_Position.z < 0.5 * cloud_height) {
shade = min(shade, mix(bottom_factor, middle_factor, gl_Position.z * 2.0 / cloud_height));
if ((fogCoord > detail_range) && (fogCoord > center_dist)) {
// More than detail_range away, so discard all sprites on opposite side of
// cloud center by shifting them beyond the view fustrum
gl_Position = vec4(0.0,0.0,10.0,1.0);
gl_FrontColor.a = 0.0;
} else {
shade = min(shade, mix(middle_factor, top_factor, gl_Position.z * 2.0 / cloud_height - 1.0));
}
//float h = gl_Position.z / cloud_height;
//if (h < 0.5) {
// shade = min(shade, mix(bottom_factor, middle_factor, smoothstep(0.0, 0.5, h)));
//} else {
// shade = min(shade, mix(middle_factor, top_factor, smoothstep(2.0 * (h - 0.5)));
// }
// Final position of the sprite
vec3 relVector = gl_Position.xyz - ep.xyz;
gl_Position = gl_ModelViewProjectionMatrix * gl_Position;
// Determine the shading of the vertex. We shade it based on it's position
// in the cloud relative to the sun, and it's vertical position in the cloud.
float shade = mix(shade_factor, top_factor, smoothstep(-0.3, 0.3, n));
//if (n < 0) {
// shade = mix(top_factor, shade_factor, abs(n));
//}
if (gl_Position.z < 0.5 * cloud_height) {
shade = min(shade, mix(bottom_factor, middle_factor, gl_Position.z * 2.0 / cloud_height));
} else {
shade = min(shade, mix(middle_factor, top_factor, gl_Position.z * 2.0 / cloud_height - 1.0));
}
//float h = gl_Position.z / cloud_height;
//if (h < 0.5) {
// shade = min(shade, mix(bottom_factor, middle_factor, smoothstep(0.0, 0.5, h)));
//} else {
// shade = min(shade, mix(middle_factor, top_factor, smoothstep(2.0 * (h - 0.5)));
// }
// Final position of the sprite
vec3 relVector = gl_Position.xyz - ep.xyz;
gl_Position = gl_ModelViewProjectionMatrix * gl_Position;
// Light at the final position
// first obtain normal to sun position
vec3 lightFull = (gl_ModelViewMatrixInverse * gl_LightSource[0].position).xyz;
vec3 lightHorizon = normalize(vec3(lightFull.x,lightFull.y, 0.0));
// Light at the final position
// yprime is the distance of the vertex into sun direction, corrected for altitude
// the altitude correction is clamped to reasonable values, sometimes altitude isn't parsed correctly, leading
// to overbright or overdark clouds
// float vertex_alt = clamp(altitude * 0.30480 + relVector.z,1000.0,10000.0);
float vertex_alt = clamp(altitude + relVector.z, 300.0, 10000.0);
float yprime = -dot(relVector, lightHorizon);
float yprime_alt = yprime -sqrt(2.0 * EarthRadius * vertex_alt);
// first obtain normal to sun position
// two times terminator width governs how quickly light fades into shadow
float terminator_width = 200000.0;
float earthShade = 0.9 * smoothstep(terminator_width+ terminator, -terminator_width + terminator, yprime_alt) + 0.1;
vec3 lightFull = (gl_ModelViewMatrixInverse * gl_LightSource[0].position).xyz;
vec3 lightHorizon = normalize(vec3(lightFull.x,lightFull.y, 0.0));
// compute the light at the position
vec4 light_diffuse;
float lightArg = (terminator-yprime_alt)/100000.0;
light_diffuse.b = light_func(lightArg, 1.330e-05, 0.264, 2.227, 1.08e-05, 1.0);
light_diffuse.g = light_func(lightArg, 3.931e-06, 0.264, 3.827, 7.93e-06, 1.0);
light_diffuse.r = light_func(lightArg, 8.305e-06, 0.161, 3.827, 3.04e-05, 1.0);
light_diffuse.a = 1.0;
intensity = (1.0 - (0.5 * (1.0 - earthShade))) * length(light_diffuse.rgb);
light_diffuse.rgb = intensity * normalize(mix(light_diffuse.rgb, shadedFogColor, (1.0 - smoothstep(0.5,0.9, min(scattering, cloud_self_shading) ))));
// correct ambient light intensity and hue before sunrise
if (earthShade < 0.8)
{
light_diffuse.rgb = intensity * normalize(mix(light_diffuse.rgb, shadedFogColor, 1.0 -smoothstep(0.1, 0.8,earthShade ) ));
}
// yprime is the distance of the vertex into sun direction, corrected for altitude
// the altitude correction is clamped to reasonable values, sometimes altitude isn't parsed correctly, leading
// to overbright or overdark clouds
// float vertex_alt = clamp(altitude * 0.30480 + relVector.z,1000.0,10000.0);
float vertex_alt = clamp(altitude + relVector.z, 300.0, 10000.0);
float yprime = -dot(relVector, lightHorizon);
float yprime_alt = yprime -sqrt(2.0 * EarthRadius * vertex_alt);
// two times terminator width governs how quickly light fades into shadow
float terminator_width = 200000.0;
float earthShade = 0.9 * smoothstep(terminator_width+ terminator, -terminator_width + terminator, yprime_alt) + 0.1;
// compute the light at the position
vec4 light_diffuse;
float lightArg = (terminator-yprime_alt)/100000.0;
light_diffuse.b = light_func(lightArg, 1.330e-05, 0.264, 2.227, 1.08e-05, 1.0);
light_diffuse.g = light_func(lightArg, 3.931e-06, 0.264, 3.827, 7.93e-06, 1.0);
light_diffuse.r = light_func(lightArg, 8.305e-06, 0.161, 3.827, 3.04e-05, 1.0);
light_diffuse.a = 1.0;
intensity = (1.0 - (0.5 * (1.0 - earthShade))) * length(light_diffuse.rgb);
light_diffuse.rgb = intensity * normalize(mix(light_diffuse.rgb, shadedFogColor, (1.0 - smoothstep(0.5,0.9, min(scattering, cloud_self_shading) ))));
// correct ambient light intensity and hue before sunrise
if (earthShade < 0.8)
{
light_diffuse.rgb = intensity * normalize(mix(light_diffuse.rgb, shadedFogColor, 1.0 -smoothstep(0.1, 0.8,earthShade ) ));
}
//gl_FrontColor = gl_LightSource[0].diffuse * shade + gl_FrontLightModelProduct.sceneColor;
//intensity = length(light_diffuse.xyz);
gl_FrontColor.rgb = intensity * shade * normalize(mix(light_diffuse.rgb, shadedFogColor, smoothstep(0.1,0.4, (1.0 - shade) ))) ;
//gl_FrontColor = gl_LightSource[0].diffuse * shade + gl_FrontLightModelProduct.sceneColor;
//intensity = length(light_diffuse.xyz);
//gl_FrontColor.a = 1.0;
//light_diffuse+ gl_FrontLightModelProduct.sceneColor;// * shade ;//+ gl_FrontLightModelProduct.sceneColor;
gl_FrontColor.rgb = intensity * shade * normalize(mix(light_diffuse.rgb, shadedFogColor, smoothstep(0.1,0.4, (1.0 - shade) ))) ;
//gl_FrontColor.a = 1.0;
//light_diffuse+ gl_FrontLightModelProduct.sceneColor;// * shade ;//+ gl_FrontLightModelProduct.sceneColor;
if ((fogCoord > (0.9 * detail_range)) && (fogCoord > center_dist)) {
// cloudlet is almost at the detail range, so fade it out.
gl_FrontColor.a = 1.0 - smoothstep(0.9 * detail_range, detail_range, fogCoord);
} else {
// 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), 1.0 - smoothstep(0.9 * range, range, fogCoord));
}
// 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), 1.0 - smoothstep(range*0.9, range, fogCoord));
//gl_BackColor = gl_FrontColor;
//gl_BackColor = gl_FrontColor;
// Fog doesn't affect clouds as much as other objects.
float fadeScale = 0.05 + 0.2 * log(fogCoord/1000.0);
if (fadeScale < 0.05) fadeScale = 0.05;
fogFactor = exp( -gl_Fog.density * fogCoord * fadeScale);
// Fog doesn't affect clouds as much as other objects.
float fadeScale = 0.05 + 0.2 * log(fogCoord/1000.0);
if (fadeScale < 0.05) fadeScale = 0.05;
fogFactor = exp( -gl_Fog.density * fogCoord * fadeScale);
// Fog doesn't affect clouds as much as other objects.
//fogFactor = exp( -gl_Fog.density * fogCoord * 0.5);
//fogFactor = clamp(fogFactor, 0.0, 1.0);
// Fog doesn't affect clouds as much as other objects.
//fogFactor = exp( -gl_Fog.density * fogCoord * 0.5);
//fogFactor = clamp(fogFactor, 0.0, 1.0);
// haze of ground haze shader is slightly bluish
hazeColor = light_diffuse.rgb;
hazeColor.r = hazeColor.r * 0.83;
hazeColor.g = hazeColor.g * 0.9;
//hazeColor = intensity * normalize(mix(hazeColor, shadedFogColor, (1.0 - smoothstep(0.5,0.9,cloud_self_shading)) ));
hazeColor = hazeColor * scattering;
// haze of ground haze shader is slightly bluish
hazeColor = light_diffuse.rgb;
hazeColor.r = hazeColor.r * 0.83;
hazeColor.g = hazeColor.g * 0.9;
//hazeColor = intensity * normalize(mix(hazeColor, shadedFogColor, (1.0 - smoothstep(0.5,0.9,cloud_self_shading)) ));
hazeColor = hazeColor * scattering;
// in sunset or sunrise conditions, do extra shading of clouds
// change haze color to blue hue for strong fogging
//intensity = length(hazeColor);
//hazeColor = intensity * normalize(mix(hazeColor, 2.0* vec3 (0.55, 0.6, 0.8), (1.0 - smoothstep(0.3,0.8,scattering))));
// in sunset or sunrise conditions, do extra shading of clouds
// change haze color to blue hue for strong fogging
//intensity = length(hazeColor);
//hazeColor = intensity * normalize(mix(hazeColor, 2.0* vec3 (0.55, 0.6, 0.8), (1.0 - smoothstep(0.3,0.8,scattering))));
//hazeColor = hazeColor * earthShade;
//gl_FrontColor.xyz = gl_FrontColor.xyz * earthShade;
// Mie correction
float Mie;
float MieFactor;
if (bottom_factor > 0.6)
{
MieFactor = dot(normalize(lightFull), normalize(relVector));
Mie = 1.5 * smoothstep(0.9,1.0, MieFactor) * smoothstep(0.6, 0.8, bottom_factor);
}
else {Mie = 0.0;}
if (Mie > 0.0)
{
hazeColor.r = mie_func(hazeColor.r, Mie);
hazeColor.g = mie_func(hazeColor.g, 0.8* Mie);
hazeColor.b = mie_func(hazeColor.b, 0.5* Mie);
gl_FrontColor.r = mie_func(gl_FrontColor.r, Mie);
gl_FrontColor.g = mie_func(gl_FrontColor.g, 0.8* Mie);
gl_FrontColor.b = mie_func(gl_FrontColor.b, 0.5*Mie);
}
gl_FrontColor.rgb = gl_FrontColor.rgb + moonLightColor * (1.0 - smoothstep(0.4, 0.5, earthShade));
hazeColor.rgb = hazeColor.rgb + moonLightColor * (1.0 - smoothstep(0.4, 0.5, earthShade));
gl_BackColor = gl_FrontColor;
//hazeColor = hazeColor * earthShade;
//gl_FrontColor.xyz = gl_FrontColor.xyz * earthShade;
// Mie correction
float Mie;
float MieFactor;
if (bottom_factor > 0.6)
{
MieFactor = dot(normalize(lightFull), normalize(relVector));
Mie = 1.5 * smoothstep(0.9,1.0, MieFactor) * smoothstep(0.6, 0.8, bottom_factor);
}
else {Mie = 0.0;}
if (Mie > 0.0)
{
hazeColor.r = mie_func(hazeColor.r, Mie);
hazeColor.g = mie_func(hazeColor.g, 0.8* Mie);
hazeColor.b = mie_func(hazeColor.b, 0.5* Mie);
gl_FrontColor.r = mie_func(gl_FrontColor.r, Mie);
gl_FrontColor.g = mie_func(gl_FrontColor.g, 0.8* Mie);
gl_FrontColor.b = mie_func(gl_FrontColor.b, 0.5*Mie);
}
gl_FrontColor.rgb = gl_FrontColor.rgb + moonLightColor * (1.0 - smoothstep(0.4, 0.5, earthShade));
hazeColor.rgb = hazeColor.rgb + moonLightColor * (1.0 - smoothstep(0.4, 0.5, earthShade));
gl_BackColor = gl_FrontColor;
}
}

80
Shaders/3dcloud.vert
View file

@ -4,6 +4,7 @@
varying float fogFactor;
uniform float range; // From /sim/rendering/clouds3d-vis-range
uniform float detail_range; // From /sim/rendering/clouds3d_detail-range
attribute vec3 usrAttr1;
attribute vec3 usrAttr2;
@ -39,45 +40,50 @@ void main(void)
// Now shift the sprite to the correct position in the cloud.
gl_Position.xyz += gl_Color.xyz;
// Determine a lighting normal based on the vertex position from the
// center of the cloud, so that sprite on the opposite side of the cloud to the sun are darker.
float n = dot(normalize(-gl_LightSource[0].position.xyz),
normalize(vec3(gl_ModelViewMatrix * vec4(- gl_Position.x, - gl_Position.y, - gl_Position.z, 0.0))));
// Determine the position - used for fog and shading calculations
vec3 ecPosition = vec3(gl_ModelViewMatrix * gl_Position);
float fogCoord = abs(ecPosition.z);
float fogCoord = length(vec3(gl_ModelViewMatrix * vec4(gl_Color.x, gl_Color.y, gl_Color.z, 1.0)));
float center_dist = length(vec3(gl_ModelViewMatrix * vec4(0.0,0.0,0.0,1.0)));
// Determine the shading of the vertex. We shade it based on it's position
// in the cloud relative to the sun, and it's vertical position in the cloud.
float shade = mix(shade_factor, top_factor, smoothstep(-0.3, 0.3, n));
//if (n < 0) {
// shade = mix(top_factor, shade_factor, abs(n));
//}
if (gl_Position.z < 0.5 * cloud_height) {
shade = min(shade, mix(bottom_factor, middle_factor, gl_Position.z * 2.0 / cloud_height));
if ((fogCoord > detail_range) && (fogCoord > center_dist)) {
// More than detail_range away, so discard all sprites on opposite side of
// cloud center by shifting them beyond the view fustrum
gl_Position = vec4(0.0,0.0,10.0,1.0);
gl_FrontColor.a = 0.0;
} else {
shade = min(shade, mix(middle_factor, top_factor, gl_Position.z * 2.0 / cloud_height - 1.0));
// Determine a lighting normal based on the vertex position from the
// center of the cloud, so that sprite on the opposite side of the cloud to the sun are darker.
float n = dot(normalize(-gl_LightSource[0].position.xyz),
normalize(vec3(gl_ModelViewMatrix * vec4(- gl_Position.x, - gl_Position.y, - gl_Position.z, 0.0))));
// Determine the shading of the vertex. We shade it based on it's position
// in the cloud relative to the sun, and it's vertical position in the cloud.
float shade = mix(shade_factor, top_factor, smoothstep(-0.3, 0.3, n));
//if (n < 0) {
// shade = mix(top_factor, shade_factor, abs(n));
//}
if (gl_Position.z < 0.5 * cloud_height) {
shade = min(shade, mix(bottom_factor, middle_factor, gl_Position.z * 2.0 / cloud_height));
} else {
shade = min(shade, mix(middle_factor, top_factor, gl_Position.z * 2.0 / cloud_height - 1.0));
}
// Final position of the sprite
gl_Position = gl_ModelViewProjectionMatrix * gl_Position;
gl_FrontColor = gl_LightSource[0].diffuse * shade + gl_FrontLightModelProduct.sceneColor;
if ((fogCoord > (0.9 * detail_range)) && (fogCoord > center_dist)) {
// cloudlet is almost at the detail range, so fade it out.
gl_FrontColor.a = 1.0 - smoothstep(0.9 * detail_range, detail_range, fogCoord);
} else {
// 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), 1.0 - smoothstep(0.9 * range, range, fogCoord));
}
gl_BackColor = gl_FrontColor;
// Fog doesn't affect clouds as much as other objects.
fogFactor = exp( -gl_Fog.density * fogCoord * 0.5);
fogFactor = clamp(fogFactor, 0.0, 1.0);
}
//float h = gl_Position.z / cloud_height;
//if (h < 0.5) {
// shade = min(shade, mix(bottom_factor, middle_factor, smoothstep(0.0, 0.5, h)));
//} else {
// shade = min(shade, mix(middle_factor, top_factor, smoothstep(2.0 * (h - 0.5)));
// }
// Final position of the sprite
gl_Position = gl_ModelViewProjectionMatrix * gl_Position;
gl_FrontColor = gl_LightSource[0].diffuse * shade + gl_FrontLightModelProduct.sceneColor;
// 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), 1.0 - smoothstep(range*0.9, range, fogCoord));
gl_BackColor = gl_FrontColor;
// Fog doesn't affect clouds as much as other objects.
fogFactor = exp( -gl_Fog.density * fogCoord * 0.5);
fogFactor = clamp(fogFactor, 0.0, 1.0);
}

1
preferences.xml
View file

@ -217,6 +217,7 @@ Started September 2000 by David Megginson, david@megginson.com
<bump-mapping type="bool" userarchive="y">false</bump-mapping>
<clouds3d-enable type="bool" userarchive="y">false</clouds3d-enable>
<clouds3d-vis-range type="float" userarchive="y">10000.0</clouds3d-vis-range>
<clouds3d-detail-range type="float" userarchive="y">10000.0</clouds3d-detail-range>
<clouds3d-density type="float" userarchive="y">0.25</clouds3d-density>
<draw-otw type="bool">true</draw-otw>
<shadows-ac type="bool" userarchive="y">false</shadows-ac>