tei/MapLibreParticleLab
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

consolidate functions to only use stops

Browse Source 
refs mapbox/mapbox-gl-style-spec#96
This commit is contained in:
Konstantin Käfer
2014-07-17 14:32:35 -07:00
parent d44742f115
commit 68f595a32b
5 changed files with 77 additions and 200 deletions
Download Patch File Download Diff File Expand all files Collapse all files

87
src/style/function_properties.cpp
View File

@@ -6,82 +6,36 @@
namespace mbgl {
template <>
bool LinearFunction<bool>::evaluate(float z) const {
return z < z_base ? slope >= 0 : z > z_base ? slope >= 0 : value;
}
template <>
float LinearFunction<float>::evaluate(float z) const {
return std::fmin(std::fmax(min, value + (z - z_base) * slope), max);
}
template <>
Color LinearFunction<Color>::evaluate(float z) const {
return {{
std::fmin(std::fmax(min[0], value[0] + (z - z_base) * slope), max[0]),
std::fmin(std::fmax(min[1], value[1] + (z - z_base) * slope), max[1]),
std::fmin(std::fmax(min[2], value[2] + (z - z_base) * slope), max[2]),
std::fmin(std::fmax(min[3], value[3] + (z - z_base) * slope), max[3])
}};
}
template <>
bool ExponentialFunction<bool>::evaluate(float z) const {
return z < z_base ? slope >= 0 : z > z_base ? slope >= 0 : value;
}
template <>
float ExponentialFunction<float>::evaluate(float z) const {
return std::fmin(std::fmax(min, value + std::pow(exp_base, (z - z_base)) * slope), max);
}
template <>
Color ExponentialFunction<Color>::evaluate(float z) const {
return {{
std::fmin(std::fmax(min[0], value[0] + float(std::pow(exp_base, (z - z_base))) * slope), max[0]),
std::fmin(std::fmax(min[1], value[1] + float(std::pow(exp_base, (z - z_base))) * slope), max[1]),
std::fmin(std::fmax(min[2], value[2] + float(std::pow(exp_base, (z - z_base))) * slope), max[2]),
std::fmin(std::fmax(min[3], value[3] + float(std::pow(exp_base, (z - z_base))) * slope), max[3])
}};
}
template <typename T>
inline T exponentialInterpolate(T smaller, T larger, const float factor);
inline T interpolate(T smaller, T larger, const float factor);
template <>
inline float exponentialInterpolate(const float smaller, const float larger, const float factor) {
// Linear interpolation if base is 0
if (smaller == 0.0f) {
return factor * larger;
}
// Exponential interpolation between the values
return smaller * std::pow(larger / smaller, factor);
inline float interpolate(const float smaller, const float larger, const float factor) {
return (smaller * (1 - factor)) + (larger * factor);
}
template <>
inline bool exponentialInterpolate(const bool smaller, const bool larger, const float factor) {
return exponentialInterpolate(float(smaller), float(larger), factor);
inline bool interpolate(const bool smaller, const bool larger, const float factor) {
return interpolate(float(smaller), float(larger), factor);
}
template <>
inline Color exponentialInterpolate(const Color smaller, const Color larger, const float factor) {
inline Color interpolate(const Color smaller, const Color larger, const float factor) {
return {{
exponentialInterpolate(smaller[0], larger[0], factor),
exponentialInterpolate(smaller[1], larger[1], factor),
exponentialInterpolate(smaller[2], larger[2], factor),
exponentialInterpolate(smaller[3], larger[3], factor)
interpolate(smaller[0], larger[0], factor),
interpolate(smaller[1], larger[1], factor),
interpolate(smaller[2], larger[2], factor),
interpolate(smaller[3], larger[3], factor)
}};
}
template <typename T>
T exponentialDefault();
inline T defaultStopsValue();
template <> bool exponentialDefault() { return true; }
template <> float exponentialDefault() { return 1.0f; }
template <> Color exponentialDefault() { return {{ 0, 0, 0, 1 }}; }
template <> inline bool defaultStopsValue() { return true; }
template <> inline float defaultStopsValue() { return 1.0f; }
template <> inline Color defaultStopsValue() { return {{ 0, 0, 0, 1 }}; }
template <typename T>
@@ -112,15 +66,22 @@ T StopsFunction<T>::evaluate(float z) const {
if (larger_z == smaller_z || larger_val == smaller_val) {
return smaller_val;
}
float factor = (z - smaller_z) / (larger_z - smaller_z);
return exponentialInterpolate<T>(smaller_val, larger_val, factor);
const float zoomDiff = larger_z - smaller_z;
const float zoomProgress = z - smaller_z;
if (base == 1.0f) {
const float t = zoomProgress / zoomDiff;
return interpolate<T>(smaller_val, larger_val, t);
} else {
const float t = (std::pow(base, zoomProgress) - 1) / (std::pow(base, zoomDiff) - 1);
return interpolate<T>(smaller_val, larger_val, t);
}
} else if (larger) {
return larger_val;
} else if (smaller) {
return smaller_val;
} else {
// No stop defined.
return exponentialDefault<T>();
return defaultStopsValue<T>();
}
}