paysages3d/lib_paysages/clouds.c

661 lines
23 KiB
C

#include "clouds.h"
#include <string.h>
#include <stdlib.h>
#include <math.h>
#include "color.h"
#include "euclid.h"
#include "lighting.h"
#include "tools.h"
#include "shared/types.h"
#define CLOUDS_MAX_LAYERS 6
#define MAX_SEGMENT_COUNT 30
typedef struct
{
Vector3 start;
Vector3 end;
double length;
} CloudSegment;
CloudsDefinition cloudsCreateDefinition()
{
CloudsDefinition result;
result.layers = layersCreate(cloudsGetLayerType(), CLOUDS_MAX_LAYERS);
return result;
}
void cloudsDeleteDefinition(CloudsDefinition* definition)
{
layersDelete(definition->layers);
}
void cloudsCopyDefinition(CloudsDefinition* source, CloudsDefinition* destination)
{
layersCopy(source->layers, destination->layers);
}
void cloudsValidateDefinition(CloudsDefinition* definition)
{
layersValidate(definition->layers);
}
void cloudsSave(PackStream* stream, CloudsDefinition* definition)
{
layersSave(stream, definition->layers);
}
void cloudsLoad(PackStream* stream, CloudsDefinition* definition)
{
layersLoad(stream, definition->layers);
}
static double _standardCoverageFunc(CloudsLayerDefinition* layer, Vector3 position)
{
if (position.y < layer->lower_altitude || position.y >= layer->lower_altitude + layer->thickness)
{
return 0.0;
}
else
{
return layer->base_coverage * curveGetValue(layer->coverage_by_altitude, (position.y - layer->lower_altitude) / layer->thickness);
}
}
CloudsLayerDefinition* cloudsLayerCreateDefinition()
{
CloudsLayerDefinition* result;
result = malloc(sizeof(CloudsLayerDefinition));
result->coverage_by_altitude = curveCreate();
result->shape_noise = noiseCreateGenerator();
result->edge_noise = noiseCreateGenerator();
result->_custom_coverage = _standardCoverageFunc;
cloudsLayerAutoPreset(result, CLOUDS_PRESET_CIRRUS);
return result;
}
void cloudsLayerDeleteDefinition(CloudsLayerDefinition* definition)
{
curveDelete(definition->coverage_by_altitude);
noiseDeleteGenerator(definition->shape_noise);
noiseDeleteGenerator(definition->edge_noise);
free(definition);
}
void cloudsLayerAutoPreset(CloudsLayerDefinition* definition, CloudsPreset preset)
{
curveClear(definition->coverage_by_altitude);
noiseClearLevels(definition->shape_noise);
noiseClearLevels(definition->edge_noise);
definition->material.base.r = 0.7;
definition->material.base.g = 0.7;
definition->material.base.b = 0.7;
definition->material.base.a = 1.0;
if (preset == CLOUDS_PRESET_STRATOCUMULUS)
{
definition->lower_altitude = 5.0;
definition->thickness = 6.0;
curveQuickAddPoint(definition->coverage_by_altitude, 0.0, 0.0);
curveQuickAddPoint(definition->coverage_by_altitude, 0.2, 1.0);
curveQuickAddPoint(definition->coverage_by_altitude, 0.5, 1.0);
curveQuickAddPoint(definition->coverage_by_altitude, 1.0, 0.0);
definition->material.reflection = 0.3;
definition->material.shininess = 0.8;
definition->hardness = 0.25;
definition->transparencydepth = 1.5;
definition->lighttraversal = 7.0;
definition->minimumlight = 0.4;
definition->shape_scaling = 10.0;
definition->edge_scaling = 0.8;
definition->edge_length = 0.3;
definition->base_coverage = 0.4;
noiseAddLevelsSimple(definition->shape_noise, 2, 1.0, 1.0);
noiseSetFunctionParams(definition->shape_noise, NOISE_FUNCTION_SIMPLEX, 0.3);
noiseAddLevelsSimple(definition->edge_noise, 8, 1.0, 1.0);
noiseSetFunctionParams(definition->edge_noise, NOISE_FUNCTION_SIMPLEX, 0.5);
}
else if (preset == CLOUDS_PRESET_CUMULUS)
{
definition->lower_altitude = 15.0;
definition->thickness = 15.0;
curveQuickAddPoint(definition->coverage_by_altitude, 0.0, 0.0);
curveQuickAddPoint(definition->coverage_by_altitude, 0.1, 1.0);
curveQuickAddPoint(definition->coverage_by_altitude, 0.4, 0.8);
curveQuickAddPoint(definition->coverage_by_altitude, 0.7, 1.0);
curveQuickAddPoint(definition->coverage_by_altitude, 1.0, 0.0);
definition->material.reflection = 0.5;
definition->material.shininess = 1.2;
definition->hardness = 0.25;
definition->transparencydepth = 1.5;
definition->lighttraversal = 8.0;
definition->minimumlight = 0.4;
definition->shape_scaling = 20.0;
definition->edge_scaling = 2.0;
definition->edge_length = 0.0;
definition->base_coverage = 0.7;
noiseAddLevelsSimple(definition->shape_noise, 7, 1.0, 1.0);
noiseSetFunctionParams(definition->shape_noise, NOISE_FUNCTION_SIMPLEX, 0.4);
}
else if (preset == CLOUDS_PRESET_CIRRUS)
{
definition->lower_altitude = 25.0;
definition->thickness = 2.0;
curveQuickAddPoint(definition->coverage_by_altitude, 0.0, 0.0);
curveQuickAddPoint(definition->coverage_by_altitude, 0.5, 1.0);
curveQuickAddPoint(definition->coverage_by_altitude, 1.0, 0.0);
definition->material.reflection = 0.4;
definition->material.shininess = 0.5;
definition->hardness = 0.0;
definition->transparencydepth = 3.0;
definition->lighttraversal = 10.0;
definition->minimumlight = 0.6;
definition->shape_scaling = 8.0;
definition->edge_scaling = 2.0;
definition->edge_length = 0.8;
definition->base_coverage = 0.6;
noiseAddLevelsSimple(definition->shape_noise, 3, 1.0, 1.0);
noiseSetFunctionParams(definition->shape_noise, NOISE_FUNCTION_SIMPLEX, 0.0);
noiseAddLevelsSimple(definition->edge_noise, 4, 1.0, 1.0);
noiseSetFunctionParams(definition->edge_noise, NOISE_FUNCTION_SIMPLEX, -0.2);
}
else if (preset == CLOUDS_PRESET_STRATUS)
{
definition->lower_altitude = 3.0;
definition->thickness = 4.0;
curveQuickAddPoint(definition->coverage_by_altitude, 0.0, 0.0);
curveQuickAddPoint(definition->coverage_by_altitude, 0.2, 1.0);
curveQuickAddPoint(definition->coverage_by_altitude, 0.8, 1.0);
curveQuickAddPoint(definition->coverage_by_altitude, 1.0, 0.0);
definition->material.reflection = 0.1;
definition->material.shininess = 0.8;
definition->hardness = 0.1;
definition->transparencydepth = 3.0;
definition->lighttraversal = 10.0;
definition->minimumlight = 0.6;
definition->shape_scaling = 8.0;
definition->edge_scaling = 2.0;
definition->edge_length = 1.0;
definition->base_coverage = 0.4;
noiseAddLevelsSimple(definition->shape_noise, 3, 1.0, 1.0);
noiseSetFunctionParams(definition->shape_noise, NOISE_FUNCTION_SIMPLEX, -0.3);
noiseAddLevelsSimple(definition->edge_noise, 4, 1.0, 1.0);
noiseSetFunctionParams(definition->edge_noise, NOISE_FUNCTION_SIMPLEX, -0.5);
}
cloudsLayerValidateDefinition(definition);
}
void cloudsLayerCopyDefinition(CloudsLayerDefinition* source, CloudsLayerDefinition* destination)
{
CloudsLayerDefinition temp;
temp = *destination;
*destination = *source;
destination->shape_noise = temp.shape_noise;
noiseCopy(source->shape_noise, destination->shape_noise);
destination->edge_noise = temp.edge_noise;
noiseCopy(source->edge_noise, destination->edge_noise);
destination->coverage_by_altitude = temp.coverage_by_altitude;
curveCopy(source->coverage_by_altitude, destination->coverage_by_altitude);
}
void cloudsLayerValidateDefinition(CloudsLayerDefinition* definition)
{
if (definition->shape_scaling < 0.0001)
{
definition->shape_scaling = 0.00001;
}
if (definition->edge_scaling < 0.0001)
{
definition->edge_scaling = 0.00001;
}
if (definition->_custom_coverage == NULL)
{
definition->_custom_coverage = _standardCoverageFunc;
}
}
void _cloudsLayerSave(PackStream* stream, CloudsLayerDefinition* layer)
{
packWriteDouble(stream, &layer->lower_altitude);
packWriteDouble(stream, &layer->thickness);
curveSave(stream, layer->coverage_by_altitude);
noiseSaveGenerator(stream, layer->shape_noise);
noiseSaveGenerator(stream, layer->edge_noise);
materialSave(stream, &layer->material);
packWriteDouble(stream, &layer->hardness);
packWriteDouble(stream, &layer->transparencydepth);
packWriteDouble(stream, &layer->lighttraversal);
packWriteDouble(stream, &layer->minimumlight);
packWriteDouble(stream, &layer->shape_scaling);
packWriteDouble(stream, &layer->edge_scaling);
packWriteDouble(stream, &layer->edge_length);
packWriteDouble(stream, &layer->base_coverage);
}
void _cloudsLayerLoad(PackStream* stream, CloudsLayerDefinition* layer)
{
packReadDouble(stream, &layer->lower_altitude);
packReadDouble(stream, &layer->thickness);
curveLoad(stream, layer->coverage_by_altitude);
noiseLoadGenerator(stream, layer->shape_noise);
noiseLoadGenerator(stream, layer->edge_noise);
materialLoad(stream, &layer->material);
packReadDouble(stream, &layer->hardness);
packReadDouble(stream, &layer->transparencydepth);
packReadDouble(stream, &layer->lighttraversal);
packReadDouble(stream, &layer->minimumlight);
packReadDouble(stream, &layer->shape_scaling);
packReadDouble(stream, &layer->edge_scaling);
packReadDouble(stream, &layer->edge_length);
packReadDouble(stream, &layer->base_coverage);
}
LayerType cloudsGetLayerType()
{
LayerType result;
result.callback_create = (LayerCallbackCreate)cloudsLayerCreateDefinition;
result.callback_delete = (LayerCallbackDelete)cloudsLayerDeleteDefinition;
result.callback_copy = (LayerCallbackCopy)cloudsLayerCopyDefinition;
result.callback_validate = (LayerCallbackValidate)cloudsLayerValidateDefinition;
result.callback_save = (LayerCallbackSave)_cloudsLayerSave;
result.callback_load = (LayerCallbackLoad)_cloudsLayerLoad;
return result;
}
static inline double _getDistanceToBorder(CloudsLayerDefinition* layer, Vector3 position)
{
double density, coverage, val;
val = noiseGet3DTotal(layer->shape_noise, position.x / layer->shape_scaling, position.y / layer->shape_scaling, position.z / layer->shape_scaling) / noiseGetMaxValue(layer->shape_noise);
coverage = layer->_custom_coverage(layer, position);
density = 0.5 * val - 0.5 + coverage;
if (density <= 0.0)
{
/* outside the main shape */
return density * layer->shape_scaling;
}
else
{
/* inside the main shape, using edge noise */
density /= coverage;
if (density < layer->edge_length)
{
density /= layer->edge_length;
val = 0.5 * noiseGet3DTotal(layer->edge_noise, position.x / layer->edge_scaling, position.y / layer->edge_scaling, position.z / layer->edge_scaling) / noiseGetMaxValue(layer->edge_noise);
val = val - 0.5 + density;
return val * (density * coverage * layer->shape_scaling + (1.0 - density) * layer->edge_scaling);
}
else
{
return density * coverage * layer->shape_scaling;
}
}
}
static inline Vector3 _getNormal(CloudsLayerDefinition* layer, Vector3 position, double detail)
{
Vector3 result = {0.0, 0.0, 0.0};
Vector3 dposition;
double val, dval;
val = _getDistanceToBorder(layer, position);
dposition.x = position.x + detail;
dposition.y = position.y;
dposition.z = position.z;
dval = val - _getDistanceToBorder(layer, dposition);
result.x += dval;
dposition.x = position.x - detail;
dval = val - _getDistanceToBorder(layer, dposition);
result.x -= dval;
dposition.x = position.x;
dposition.y = position.y + detail;
dval = val - _getDistanceToBorder(layer, dposition);
result.y += dval;
dposition.y = position.y - detail;
dval = val - _getDistanceToBorder(layer, dposition);
result.y -= dval;
dposition.y = position.y;
dposition.z = position.z + detail;
dval = val - _getDistanceToBorder(layer, dposition);
result.z += dval;
dposition.z = position.z - detail;
dval = val - _getDistanceToBorder(layer, dposition);
result.z -= dval;
return v3Normalize(result);
}
/**
* Optimize the search limits in a layer.
*
* @param layer The cloud layer
* @param start Start of the search to optimize
* @param end End of the search to optimize
* @return 0 if the search is useless
*/
static int _optimizeSearchLimits(CloudsLayerDefinition* layer, Vector3* start, Vector3* end)
{
Vector3 diff;
if (start->y > layer->lower_altitude + layer->thickness)
{
if (end->y >= layer->lower_altitude + layer->thickness)
{
return 0;
}
else
{
diff = v3Sub(*end, *start);
*start = v3Add(*start, v3Scale(diff, (layer->lower_altitude + layer->thickness - start->y) / diff.y));
if (end->y < layer->lower_altitude)
{
*end = v3Add(*end, v3Scale(diff, (layer->lower_altitude - end->y) / diff.y));
}
}
}
else if (start->y < layer->lower_altitude)
{
if (end->y <= layer->lower_altitude)
{
return 0;
}
else
{
diff = v3Sub(*end, *start);
*start = v3Add(*start, v3Scale(diff, (layer->lower_altitude - start->y) / diff.y));
if (end->y >= layer->lower_altitude + layer->thickness)
{
*end = v3Add(*end, v3Scale(diff, (layer->lower_altitude + layer->thickness - end->y) / diff.y));
}
}
}
else /* start is inside layer */
{
diff = v3Sub(*end, *start);
if (end->y > layer->lower_altitude + layer->thickness)
{
*end = v3Add(*start, v3Scale(diff, (layer->lower_altitude + layer->thickness - start->y) / diff.y));
}
else if (end->y < layer->lower_altitude)
{
*end = v3Add(*start, v3Scale(diff, (layer->lower_altitude - start->y) / diff.y));
}
}
/* TODO Limit the search length */
return 1;
}
/**
* Go through the cloud layer to find segments (parts of the lookup that are inside the cloud).
*
* @param definition The cloud layer
* @param renderer The renderer environment
* @param start Start position of the lookup (already optimized)
* @param direction Normalized direction of the lookup
* @param detail Level of noise detail required
* @param max_segments Maximum number of segments to collect
* @param max_inside_length Maximum length to spend inside the cloud
* @param max_total_length Maximum lookup length
* @param inside_length Resulting length inside cloud (sum of all segments length)
* @param total_length Resulting lookup length
* @param out_segments Allocated space to fill found segments
* @return Number of segments found
*/
static int _findSegments(CloudsLayerDefinition* definition, Renderer* renderer, Vector3 start, Vector3 direction, double detail, int max_segments, double max_inside_length, double max_total_length, double* inside_length, double* total_length, CloudSegment* out_segments)
{
int inside, segment_count;
double current_total_length, current_inside_length;
double step_length, segment_length, remaining_length;
double noise_distance, last_noise_distance;
Vector3 walker, step, segment_start;
double render_precision;
if (max_segments <= 0)
{
return 0;
}
render_precision = 15.2 - 1.5 * (double)renderer->render_quality;
render_precision = render_precision * definition->shape_scaling / 150.0;
if (render_precision > max_total_length / 10.0)
{
render_precision = max_total_length / 10.0;
}
else if (render_precision < max_total_length / 2000.0)
{
render_precision = max_total_length / 2000.0;
}
segment_count = 0;
current_total_length = 0.0;
current_inside_length = 0.0;
segment_length = 0.0;
walker = start;
noise_distance = _getDistanceToBorder(definition, start) * render_precision;
inside = (noise_distance > 0.0) ? 1 : 0;
step = v3Scale(direction, render_precision);
do
{
walker = v3Add(walker, step);
step_length = v3Norm(step);
last_noise_distance = noise_distance;
noise_distance = _getDistanceToBorder(definition, walker) * render_precision;
current_total_length += step_length;
if (current_total_length >= max_total_length || current_inside_length > max_inside_length)
{
noise_distance = 0.0;
}
if (noise_distance > 0.0)
{
if (inside)
{
// inside the cloud
segment_length += step_length;
current_inside_length += step_length;
step = v3Scale(direction, (noise_distance < render_precision) ? render_precision : noise_distance);
}
else
{
// entering the cloud
inside = 1;
segment_length = step_length * noise_distance / (noise_distance - last_noise_distance);
segment_start = v3Add(walker, v3Scale(direction, -segment_length));
current_inside_length += segment_length;
step = v3Scale(direction, render_precision);
}
}
else
{
if (inside)
{
// exiting the cloud
remaining_length = step_length * last_noise_distance / (last_noise_distance - noise_distance);
segment_length += remaining_length;
current_inside_length += remaining_length;
out_segments->start = segment_start;
out_segments->end = v3Add(walker, v3Scale(direction, remaining_length - step_length));
out_segments->length = segment_length;
out_segments++;
if (++segment_count >= max_segments)
{
break;
}
inside = 0;
step = v3Scale(direction, render_precision);
}
else
{
// searching for a cloud
step = v3Scale(direction, (noise_distance > -render_precision) ? render_precision : -noise_distance);
}
}
} while (inside || (walker.y <= definition->lower_altitude + definition->thickness + 0.001 && walker.y >= definition->lower_altitude - 0.001 && current_total_length < max_total_length && current_inside_length < max_inside_length));
*total_length = current_total_length;
*inside_length = current_inside_length;
return segment_count;
}
static Color _applyLayerLighting(CloudsLayerDefinition* definition, Renderer* renderer, Vector3 position, double detail)
{
Vector3 normal;
Color col1, col2;
LightStatus light;
normal = _getNormal(definition, position, 3.0);
if (renderer->render_quality > 5)
{
normal = v3Add(normal, _getNormal(definition, position, 2.0));
normal = v3Add(normal, _getNormal(definition, position, 1.0));
}
if (renderer->render_quality > 5)
{
normal = v3Add(normal, _getNormal(definition, position, 0.5));
}
normal = v3Scale(v3Normalize(normal), definition->hardness);
renderer->getLightStatus(renderer, &light, position);
col1 = renderer->applyLightStatus(renderer, &light, position, normal, definition->material);
col2 = renderer->applyLightStatus(renderer, &light, position, v3Scale(normal, -1.0), definition->material);
col1.r = (col1.r + col2.r) / 2.0;
col1.g = (col1.g + col2.g) / 2.0;
col1.b = (col1.b + col2.b) / 2.0;
col1.a = (col1.a + col2.a) / 2.0;
return col1;
}
Color cloudsApplyLayer(CloudsLayerDefinition* definition, Color base, Renderer* renderer, Vector3 start, Vector3 end)
{
int i, segment_count;
double max_length, detail, total_length, inside_length;
Vector3 direction;
Color col;
CloudSegment segments[MAX_SEGMENT_COUNT];
if (!_optimizeSearchLimits(definition, &start, &end))
{
return base;
}
direction = v3Sub(end, start);
max_length = v3Norm(direction);
direction = v3Normalize(direction);
detail = renderer->getPrecision(renderer, start) / definition->shape_scaling;
segment_count = _findSegments(definition, renderer, start, direction, detail, MAX_SEGMENT_COUNT, definition->transparencydepth * (double)renderer->render_quality, max_length, &inside_length, &total_length, segments);
for (i = segment_count - 1; i >= 0; i--)
{
col = _applyLayerLighting(definition, renderer, segments[i].start, detail);
col.a = 1.0;
col = renderer->atmosphere->applyAerialPerspective(renderer, start, col);
col.a = (segments[i].length >= definition->transparencydepth) ? 1.0 : (segments[i].length / definition->transparencydepth);
colorMask(&base, &col);
}
if (inside_length >= definition->transparencydepth)
{
col.a = 1.0;
}
return base;
}
/*static int _cmpLayer(const void* layer1, const void* layer2)
{
return (((CloudsLayerDefinition*)layer1)->lower_altitude > ((CloudsLayerDefinition*)layer2)->lower_altitude) ? -1 : 1;
}*/
Color cloudsApply(CloudsDefinition* definition, Color base, Renderer* renderer, Vector3 start, Vector3 end)
{
int i, n;
n = layersCount(definition->layers);
if (n < 1)
{
return base;
}
/* TODO Iter layers in sorted order */
for (i = 0; i < n; i++)
{
base = cloudsApplyLayer(layersGetLayer(definition->layers, i), base, renderer, start, end);
}
return base;
}
Color cloudsLayerFilterLight(CloudsLayerDefinition* definition, Renderer* renderer, Color light, Vector3 location, Vector3 light_location, Vector3 direction_to_light)
{
double inside_depth, total_depth, factor;
CloudSegment segments[MAX_SEGMENT_COUNT];
_optimizeSearchLimits(definition, &location, &light_location);
_findSegments(definition, renderer, location, direction_to_light, 0.1, MAX_SEGMENT_COUNT, definition->lighttraversal, v3Norm(v3Sub(light_location, location)), &inside_depth, &total_depth, segments);
if (definition->lighttraversal < 0.0001)
{
factor = 0.0;
}
else
{
factor = inside_depth / definition->lighttraversal;
if (factor > 1.0)
{
factor = 1.0;
}
}
factor = 1.0 - (1.0 - definition->minimumlight) * factor;
light.r = light.r * factor;
light.g = light.g * factor;
light.b = light.b * factor;
return light;
}
Color cloudsFilterLight(CloudsDefinition* definition, Renderer* renderer, Color light, Vector3 location, Vector3 light_location, Vector3 direction_to_light)
{
int i, n;
/* TODO Iter layers in sorted order */
n = layersCount(definition->layers);
for (i = 0; i < n; i++)
{
light = cloudsLayerFilterLight(layersGetLayer(definition->layers, i), renderer, light, location, light_location, direction_to_light);
}
return light;
}