Michaël Lemaire
d8dfb6c1ab
git-svn-id: https://subversion.assembla.com/svn/thunderk/paysages@196 b1fd45b6-86a6-48da-8261-f70d1f35bdcc
455 lines
13 KiB
C
455 lines
13 KiB
C
#include <math.h>
|
|
|
|
#include "shared/types.h"
|
|
#include "shared/functions.h"
|
|
#include "shared/constants.h"
|
|
#include "shared/globals.h"
|
|
#include "clouds.h"
|
|
|
|
#define MAX_LAYERS 10
|
|
|
|
static int _layers_count = 0;
|
|
static CloudsDefinition _layers[MAX_LAYERS];
|
|
static CloudsQuality _quality;
|
|
static CloudsEnvironment _environment;
|
|
|
|
typedef struct
|
|
{
|
|
Vector3 start;
|
|
Vector3 end;
|
|
double length;
|
|
} CloudSegment;
|
|
|
|
void cloudsInit()
|
|
{
|
|
_layers_count = 0;
|
|
|
|
_quality.precision = 0.5;
|
|
}
|
|
|
|
void cloudsSave(FILE* f)
|
|
{
|
|
int i;
|
|
CloudsDefinition* layer;
|
|
|
|
toolsSaveInt(f, _layers_count);
|
|
for (i = 0; i < _layers_count; i++)
|
|
{
|
|
layer = _layers + i;
|
|
toolsSaveDouble(f, layer->ycenter);
|
|
toolsSaveDouble(f, layer->ymin);
|
|
toolsSaveDouble(f, layer->ymax);
|
|
noiseSave(layer->noise, f);
|
|
colorSave(layer->color, f);
|
|
toolsSaveDouble(f, layer->scaling);
|
|
toolsSaveDouble(f, layer->coverage);
|
|
}
|
|
}
|
|
|
|
void cloudsLoad(FILE* f)
|
|
{
|
|
int i;
|
|
CloudsDefinition* layer;
|
|
|
|
_layers_count = toolsLoadInt(f);
|
|
for (i = 0; i < _layers_count; i++)
|
|
{
|
|
layer = _layers + i;
|
|
layer->ycenter = toolsLoadDouble(f);
|
|
layer->ymin = toolsLoadDouble(f);
|
|
layer->ymax = toolsLoadDouble(f);
|
|
noiseLoad(layer->noise, f);
|
|
layer->color = colorLoad(f);
|
|
layer->scaling = toolsLoadDouble(f);
|
|
layer->coverage = toolsLoadDouble(f);
|
|
}
|
|
}
|
|
|
|
int cloudsGetLayerCount()
|
|
{
|
|
return _layers_count;
|
|
}
|
|
|
|
int cloudsAddLayer()
|
|
{
|
|
CloudsDefinition* layer;
|
|
|
|
layer = _layers + _layers_count;
|
|
layer->noise = noiseCreateGenerator();
|
|
layer->coverage = 0.0;
|
|
|
|
return _layers_count++;
|
|
}
|
|
|
|
void cloudsDeleteLayer(int layer)
|
|
{
|
|
/* TODO */
|
|
}
|
|
|
|
CloudsDefinition cloudsCreateDefinition()
|
|
{
|
|
CloudsDefinition result;
|
|
|
|
result.color = COLOR_WHITE;
|
|
result.coverage = 0.0;
|
|
result.noise = noiseCreateGenerator();
|
|
result.scaling = 1.0;
|
|
result.ymin = 0.0;
|
|
result.ycenter = 0.0;
|
|
result.ymax = 0.0;
|
|
|
|
return result;
|
|
}
|
|
|
|
void cloudsDeleteDefinition(CloudsDefinition definition)
|
|
{
|
|
noiseDeleteGenerator(definition.noise);
|
|
}
|
|
|
|
void cloudsCopyDefinition(CloudsDefinition source, CloudsDefinition* destination)
|
|
{
|
|
NoiseGenerator* noise;
|
|
|
|
noise = destination->noise;
|
|
*destination = source;
|
|
destination->noise = noise;
|
|
noiseCopy(source.noise, destination->noise);
|
|
}
|
|
|
|
void cloudsSetDefinition(int layer, CloudsDefinition definition)
|
|
{
|
|
CloudsDefinition* destination;
|
|
|
|
if (layer >= 0 && layer < _layers_count)
|
|
{
|
|
destination = _layers + layer;
|
|
cloudsCopyDefinition(definition, destination);
|
|
if (destination->coverage < 0.5)
|
|
{
|
|
noiseNormalizeHeight(destination->noise, -1.0, destination->coverage * 2.0, 0);
|
|
}
|
|
else
|
|
{
|
|
noiseNormalizeHeight(destination->noise, -(1.0 - destination->coverage) * 2.0, 1.0, 0);
|
|
}
|
|
}
|
|
}
|
|
|
|
CloudsDefinition cloudsGetDefinition(int layer)
|
|
{
|
|
return _layers[layer];
|
|
}
|
|
|
|
void cloudsSetQuality(CloudsQuality quality)
|
|
{
|
|
_quality = quality;
|
|
}
|
|
|
|
CloudsQuality cloudsGetQuality()
|
|
{
|
|
return _quality;
|
|
}
|
|
|
|
static inline double _getDistanceToBorder(CloudsDefinition* layer, Vector3 position, double detail)
|
|
{
|
|
double val, min;
|
|
|
|
if (position.y > layer->ycenter)
|
|
{
|
|
min = (position.y - layer->ycenter) / (layer->ymax - layer->ycenter);
|
|
}
|
|
else
|
|
{
|
|
min = (layer->ycenter - position.y) / (layer->ycenter - layer->ymin);
|
|
}
|
|
|
|
val = noiseGet3DDetail(layer->noise, position.x, position.y, position.z, detail);
|
|
|
|
return (val - min) * layer->scaling;
|
|
}
|
|
|
|
static inline Vector3 _getNormal(CloudsDefinition* layer, Vector3 position, double detail)
|
|
{
|
|
Vector3 result = {0.0, 0.0, 0.0};
|
|
double val, dval;
|
|
|
|
val = noiseGet3DDetail(layer->noise, position.x, position.y, position.z, detail);
|
|
|
|
dval = val - noiseGet3DDetail(layer->noise, position.x + detail, position.y, position.z, detail);
|
|
result.x += dval;
|
|
|
|
dval = val - noiseGet3DDetail(layer->noise, position.x - detail, position.y, position.z, detail);
|
|
result.x -= dval;
|
|
|
|
dval = val - noiseGet3DDetail(layer->noise, position.x, position.y + detail, position.z, detail);
|
|
result.y += dval;
|
|
|
|
dval = val - noiseGet3DDetail(layer->noise, position.x, position.y - detail, position.z, detail);
|
|
result.y -= dval;
|
|
|
|
dval = val - noiseGet3DDetail(layer->noise, position.x, position.y, position.z + detail, detail);
|
|
result.z += dval;
|
|
|
|
dval = val - noiseGet3DDetail(layer->noise, position.x, position.y, position.z - detail, detail);
|
|
result.z -= dval;
|
|
|
|
return 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(CloudsDefinition* layer, Vector3* start, Vector3* end)
|
|
{
|
|
Vector3 diff;
|
|
|
|
if (start->y > layer->ymax)
|
|
{
|
|
if (end->y >= layer->ymax)
|
|
{
|
|
return 0;
|
|
}
|
|
else
|
|
{
|
|
diff = v3Sub(*end, *start);
|
|
*start = v3Add(*start, v3Scale(diff, (layer->ymax - start->y) / diff.y));
|
|
if (end->y < layer->ymin)
|
|
{
|
|
*end = v3Add(*end, v3Scale(diff, (layer->ymin - end->y) / diff.y));
|
|
}
|
|
}
|
|
}
|
|
else if (start->y < layer->ymin)
|
|
{
|
|
if (end->y <= layer->ymin)
|
|
{
|
|
return 0;
|
|
}
|
|
else
|
|
{
|
|
diff = v3Sub(*end, *start);
|
|
*start = v3Add(*start, v3Scale(diff, (layer->ymin - start->y) / diff.y));
|
|
if (end->y > layer->ymax)
|
|
{
|
|
*end = v3Add(*end, v3Scale(diff, (layer->ymax - end->y) / diff.y));
|
|
}
|
|
}
|
|
}
|
|
else /* start is inside layer */
|
|
{
|
|
diff = v3Sub(*end, *start);
|
|
if (end->y > layer->ymax)
|
|
{
|
|
*end = v3Add(*start, v3Scale(diff, (layer->ymax - start->y) / diff.y));
|
|
}
|
|
else if (end->y < layer->ymin)
|
|
{
|
|
*end = v3Add(*start, v3Scale(diff, (layer->ymin - 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 quality Render quality
|
|
* @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(CloudsDefinition* definition, CloudsQuality* quality, 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;
|
|
|
|
if (max_segments <= 0)
|
|
{
|
|
return 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, detail) * quality->precision;
|
|
inside = (noise_distance > 0.0) ? 1 : 0;
|
|
step = v3Scale(direction, quality->precision);
|
|
|
|
do
|
|
{
|
|
walker = v3Add(walker, step);
|
|
step_length = v3Norm(step);
|
|
last_noise_distance = noise_distance;
|
|
noise_distance = _getDistanceToBorder(definition, walker, detail) * quality->precision;
|
|
current_total_length += step_length;
|
|
|
|
if (noise_distance > 0.0)
|
|
{
|
|
if (inside)
|
|
{
|
|
// inside the cloud
|
|
segment_length += step_length;
|
|
current_inside_length += step_length;
|
|
step = v3Scale(direction, (noise_distance < quality->precision) ? quality->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, quality->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, quality->precision);
|
|
}
|
|
else
|
|
{
|
|
// searching for a cloud
|
|
step = v3Scale(direction, (noise_distance > -quality->precision) ? quality->precision : -noise_distance);
|
|
}
|
|
}
|
|
} while (inside || (walker.y <= definition->ymax + 0.001 && walker.y >= definition->ymin - 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(CloudsDefinition* definition, CloudsQuality* quality, Vector3 position, Color base, double detail)
|
|
{
|
|
Vector3 direction, normal;
|
|
double inside_depth, total_depth;
|
|
CloudSegment segments[20];
|
|
Color result;
|
|
|
|
normal = _getNormal(definition, position, 0.5);
|
|
normal = v3Add(normal, _getNormal(definition, position, 0.2));
|
|
normal = v3Add(normal, _getNormal(definition, position, 0.1));
|
|
result = lightingApply(position, normal, 0.0, base, 0.3, 0.1);
|
|
|
|
direction = sun_direction_inv;
|
|
detail = (detail < 0.1) ? 0.1 : detail;
|
|
/* FIXME Dont hard-code max_total_length */
|
|
_findSegments(definition, quality, position, direction, detail, 20, 50.0, 300.0, &inside_depth, &total_depth, segments);
|
|
|
|
inside_depth *= 0.02;
|
|
if (inside_depth > 1.0)
|
|
{
|
|
inside_depth = 1.0;
|
|
}
|
|
|
|
result.r = base.r * sun_color_lum * (0.9 - 0.2 * inside_depth) + result.r * (0.1 + 0.1 * inside_depth) + (0.1 - inside_depth * 0.1) * sun_color_lum;
|
|
result.g = base.g * sun_color_lum * (0.9 - 0.2 * inside_depth) + result.g * (0.1 + 0.1 * inside_depth) + (0.1 - inside_depth * 0.1) * sun_color_lum;
|
|
result.b = base.b * sun_color_lum * (0.9 - 0.2 * inside_depth) + result.b * (0.1 + 0.1 * inside_depth) + (0.1 - inside_depth * 0.1) * sun_color_lum;
|
|
|
|
return result;
|
|
}
|
|
|
|
Color cloudsGetColorCustom(Vector3 start, Vector3 end, CloudsDefinition* definition, CloudsQuality* quality, CloudsEnvironment* environment)
|
|
{
|
|
int i, segment_count;
|
|
double max_length, detail, total_length, inside_length;
|
|
Vector3 direction;
|
|
Color result, col;
|
|
CloudSegment segments[20];
|
|
|
|
if (quality == NULL)
|
|
{
|
|
quality = &_quality;
|
|
}
|
|
if (environment == NULL)
|
|
{
|
|
environment = &_environment;
|
|
}
|
|
|
|
if (!_optimizeSearchLimits(definition, &start, &end))
|
|
{
|
|
return COLOR_TRANSPARENT;
|
|
}
|
|
|
|
direction = v3Sub(end, start);
|
|
max_length = v3Norm(direction);
|
|
direction = v3Normalize(direction);
|
|
result = COLOR_TRANSPARENT;
|
|
|
|
/* TODO Flexible precision */
|
|
detail = renderGetPrecision(start) / definition->scaling;
|
|
|
|
segment_count = _findSegments(definition, quality, start, direction, detail, 20, 60.0, max_length, &inside_length, &total_length, segments);
|
|
for (i = 0; i < segment_count; i++)
|
|
{
|
|
col = _applyLayerLighting(definition, quality, segments[i].start, definition->color, detail);
|
|
col.a = (segments[i].length >= 50.0) ? 1.0 : (segments[i].length / 50.0);
|
|
colorMask(&result, &col);
|
|
}
|
|
return result;
|
|
}
|
|
|
|
Color cloudsGetColor(Vector3 start, Vector3 end)
|
|
{
|
|
int i;
|
|
Color layer_color, result;
|
|
|
|
if (end.y < start.y)
|
|
{
|
|
return cloudsGetColor(end, start);
|
|
}
|
|
|
|
if (_layers_count < 1 || end.y - start.y < 0.001)
|
|
{
|
|
return COLOR_TRANSPARENT;
|
|
}
|
|
|
|
result = COLOR_TRANSPARENT;
|
|
for (i = 0; i < _layers_count; i++)
|
|
{
|
|
layer_color = cloudsGetColorCustom(start, end, _layers + i, &_quality, &_environment);
|
|
if (layer_color.a > 0.0)
|
|
{
|
|
colorMask(&result, &layer_color);
|
|
}
|
|
}
|
|
|
|
return result;
|
|
}
|