Skip to content
Permalink
Browse files
Improve shadow rendering with non-default camera FOV (#11385)
* Adjust minimum filter radius for perspective

* Expand shadow frustum when camera FOV changes, reuse FOV distance adjustment from numeric.cpp

* Read shadow_soft_radius setting as float

* Use adaptive filter radius to accomodate for PSM distortion

* Adjust filter radius for texture resolution
  • Loading branch information
x2048 committed Jul 11, 2021
1 parent 1d25d1f commit f5706d444b02ccc1fcd854968087172d50cfcca2
@@ -181,9 +181,14 @@ float getDeltaPerspectiveFactor(float l)

float getPenumbraRadius(sampler2D shadowsampler, vec2 smTexCoord, float realDistance, float multiplier)
{
float baseLength = getBaseLength(smTexCoord);
float perspectiveFactor;

// Return fast if sharp shadows are requested
if (SOFTSHADOWRADIUS <= 1.0)
return SOFTSHADOWRADIUS;
if (SOFTSHADOWRADIUS <= 1.0) {
perspectiveFactor = getDeltaPerspectiveFactor(baseLength);
return max(2 * length(smTexCoord.xy) * 2048 / f_textureresolution / pow(perspectiveFactor, 3), SOFTSHADOWRADIUS);
}

vec2 clampedpos;
float texture_size = 1.0 / (2048 /*f_textureresolution*/ * 0.5);
@@ -192,8 +197,6 @@ float getPenumbraRadius(sampler2D shadowsampler, vec2 smTexCoord, float realDist
float pointDepth;
float maxRadius = SOFTSHADOWRADIUS * 5.0 * multiplier;

float baseLength = getBaseLength(smTexCoord);
float perspectiveFactor;
float bound = clamp(PCFBOUND * (1 - baseLength), 0.5, PCFBOUND);
int n = 0;

@@ -211,9 +214,10 @@ float getPenumbraRadius(sampler2D shadowsampler, vec2 smTexCoord, float realDist
}

depth = depth / n;

depth = pow(clamp(depth, 0.0, 1000.0), 1.6) / 0.001;
return max(0.5, depth * maxRadius);

perspectiveFactor = getDeltaPerspectiveFactor(baseLength);
return max(length(smTexCoord.xy) * 2 * 2048 / f_textureresolution / pow(perspectiveFactor, 3), depth * maxRadius);
}

#ifdef POISSON_FILTER
@@ -740,7 +740,7 @@ ShaderInfo ShaderSource::generateShader(const std::string &name,
s32 shadow_filter = g_settings->getS32("shadow_filters");
shaders_header << "#define SHADOW_FILTER " << shadow_filter << "\n";

float shadow_soft_radius = g_settings->getS32("shadow_soft_radius");
float shadow_soft_radius = g_settings->getFloat("shadow_soft_radius");
if (shadow_soft_radius < 1.0f)
shadow_soft_radius = 1.0f;
shaders_header << "#define SOFTSHADOWRADIUS " << shadow_soft_radius << "\n";
@@ -33,29 +33,34 @@ void DirectionalLight::createSplitMatrices(const Camera *cam)
v3f newCenter;
v3f look = cam->getDirection();

// camera view tangents
float tanFovY = tanf(cam->getFovY() * 0.5f);
float tanFovX = tanf(cam->getFovX() * 0.5f);

// adjusted frustum boundaries
float sfNear = shadow_frustum.zNear;
float sfFar = adjustDist(shadow_frustum.zFar, cam->getFovY());

// adjusted camera positions
v3f camPos2 = cam->getPosition();
v3f camPos = v3f(camPos2.X - cam->getOffset().X * BS,
camPos2.Y - cam->getOffset().Y * BS,
camPos2.Z - cam->getOffset().Z * BS);
camPos += look * shadow_frustum.zNear;
camPos2 += look * shadow_frustum.zNear;
float end = shadow_frustum.zNear + shadow_frustum.zFar;
newCenter = camPos + look * (shadow_frustum.zNear + 0.05f * end);
v3f world_center = camPos2 + look * (shadow_frustum.zNear + 0.05f * end);
// Create a vector to the frustum far corner
// @Liso: move all vars we can outside the loop.
float tanFovY = tanf(cam->getFovY() * 0.5f);
float tanFovX = tanf(cam->getFovX() * 0.5f);
camPos += look * sfNear;
camPos2 += look * sfNear;

const v3f &viewUp = cam->getCameraNode()->getUpVector();
// viewUp.normalize();
// center point of light frustum
float end = sfNear + sfFar;
newCenter = camPos + look * (sfNear + 0.05f * end);
v3f world_center = camPos2 + look * (sfNear + 0.05f * end);

// Create a vector to the frustum far corner
const v3f &viewUp = cam->getCameraNode()->getUpVector();
v3f viewRight = look.crossProduct(viewUp);
// viewRight.normalize();

v3f farCorner = look + viewRight * tanFovX + viewUp * tanFovY;
// Compute the frustumBoundingSphere radius
v3f boundVec = (camPos + farCorner * shadow_frustum.zFar) - newCenter;
v3f boundVec = (camPos + farCorner * sfFar) - newCenter;
radius = boundVec.getLength() * 2.0f;
// boundVec.getLength();
float vvolume = radius * 2.0f;
@@ -159,16 +159,21 @@ bool isBlockInSight(v3s16 blockpos_b, v3f camera_pos, v3f camera_dir,
return true;
}

s16 adjustDist(s16 dist, float zoom_fov)
inline float adjustDist(float dist, float zoom_fov)
{
// 1.775 ~= 72 * PI / 180 * 1.4, the default FOV on the client.
// The heuristic threshold for zooming is half of that.
static constexpr const float threshold_fov = 1.775f / 2.0f;
if (zoom_fov < 0.001f || zoom_fov > threshold_fov)
return dist;

return std::round(dist * std::cbrt((1.0f - std::cos(threshold_fov)) /
(1.0f - std::cos(zoom_fov / 2.0f))));
return dist * std::cbrt((1.0f - std::cos(threshold_fov)) /
(1.0f - std::cos(zoom_fov / 2.0f)));
}

s16 adjustDist(s16 dist, float zoom_fov)
{
return std::round(adjustDist((float)dist, zoom_fov));
}

void setPitchYawRollRad(core::matrix4 &m, const v3f &rot)

0 comments on commit f5706d4

Please sign in to comment.