From 03c11a73d86b2cd6fd204f9eef1cdb9d33ab88c6 Mon Sep 17 00:00:00 2001 From: paramat Date: Sat, 18 Nov 2017 00:22:15 +0000 Subject: [PATCH] Light curve: Add and tune mid boost gaussian Create a closer match to the light curve of 0.4.16 stable. Results in darker shadows while maintaining the 'brightness' and light spread. --- builtin/settingtypes.txt | 14 +++++++++++++- src/defaultsettings.cpp | 5 ++++- src/light.cpp | 32 +++++++++++++++++--------------- 3 files changed, 34 insertions(+), 17 deletions(-) diff --git a/builtin/settingtypes.txt b/builtin/settingtypes.txt index 74c71a1ec..994b49ed2 100644 --- a/builtin/settingtypes.txt +++ b/builtin/settingtypes.txt @@ -574,9 +574,21 @@ zoom_fov (Field of view for zoom) int 15 7 160 # This setting is for the client only and is ignored by the server. display_gamma (Gamma) float 1.0 0.5 3.0 +# Gradient of light curve at minimum light level. lighting_alpha (Darkness sharpness) float 0.0 0.0 4.0 -lighting_beta (Lightness sharpness) float 0.0 0.0 4.0 +# Gradient of light curve at maximum light level. +lighting_beta (Lightness sharpness) float 1.5 0.0 4.0 + +# Strength of light curve mid-boost. +lighting_boost (Light curve mid boost) float 0.2 0.0 1.0 + +# Center of light curve mid-boost. +lighting_boost_center (Light curve mid boost center) float 0.5 0.0 1.0 + +# Spread of light curve mid-boost. +# Standard deviation of the mid-boost gaussian. +lighting_boost_spread (Light curve mid boost spread) float 0.2 0.0 1.0 # Path to texture directory. All textures are first searched from here. texture_path (Texture path) path diff --git a/src/defaultsettings.cpp b/src/defaultsettings.cpp index 1a2656f0e..41f018b78 100644 --- a/src/defaultsettings.cpp +++ b/src/defaultsettings.cpp @@ -163,8 +163,11 @@ void set_default_settings(Settings *settings) settings->setDefault("connected_glass", "false"); settings->setDefault("smooth_lighting", "true"); settings->setDefault("lighting_alpha", "0.0"); - settings->setDefault("lighting_beta", "0.0"); + settings->setDefault("lighting_beta", "1.5"); settings->setDefault("display_gamma", "1.0"); + settings->setDefault("lighting_boost", "0.2"); + settings->setDefault("lighting_boost_center", "0.5"); + settings->setDefault("lighting_boost_spread", "0.2"); settings->setDefault("texture_path", ""); settings->setDefault("shader_path", ""); settings->setDefault("video_driver", "opengl"); diff --git a/src/light.cpp b/src/light.cpp index 575bc2c72..4a20c58ab 100644 --- a/src/light.cpp +++ b/src/light.cpp @@ -24,38 +24,40 @@ with this program; if not, write to the Free Software Foundation, Inc., #ifndef SERVER -// Length of LIGHT_MAX+1 means LIGHT_MAX is the last value. +// Length of LIGHT_MAX + 1 means LIGHT_MAX is the last value. // LIGHT_SUN is read as LIGHT_MAX from here. +u8 light_LUT[LIGHT_MAX + 1]; -u8 light_LUT[LIGHT_MAX+1]; - -// the const ref to light_LUT is what is actually used in the code. +// The const ref to light_LUT is what is actually used in the code const u8 *light_decode_table = light_LUT; -/** Initialize or update the light value tables using the specified \p gamma. - */ +// Initialize or update the light value tables using the specified gamma void set_light_table(float gamma) { -// lighting curve derivatives +// Lighting curve derivatives const float alpha = g_settings->getFloat("lighting_alpha"); const float beta = g_settings->getFloat("lighting_beta"); -// lighting curve coefficients - const float a = alpha + beta - 2; - const float b = 3 - 2 * alpha - beta; +// Lighting curve coefficients + const float a = alpha + beta - 2.0f; + const float b = 3.0f - 2.0f * alpha - beta; const float c = alpha; -// gamma correction - gamma = rangelim(gamma, 0.5, 3.0); +// Mid boost + const float d = g_settings->getFloat("lighting_boost"); + const float e = g_settings->getFloat("lighting_boost_center"); + const float f = g_settings->getFloat("lighting_boost_spread"); +// Gamma correction + gamma = rangelim(gamma, 0.5f, 3.0f); for (size_t i = 0; i < LIGHT_MAX; i++) { float x = i; x /= LIGHT_MAX; float brightness = a * x * x * x + b * x * x + c * x; - brightness = powf(brightness, 1.0 / gamma); - light_LUT[i] = rangelim((u32)(255 * brightness), 0, 255); + float boost = d * std::exp(-((x - e) * (x - e)) / (2.0f * f * f)); + brightness = powf(brightness + boost, 1.0f / gamma); + light_LUT[i] = rangelim((u32)(255.0f * brightness), 0, 255); if (i > 1 && light_LUT[i] <= light_LUT[i - 1]) light_LUT[i] = light_LUT[i - 1] + 1; } light_LUT[LIGHT_MAX] = 255; } #endif -