paysages : Terrain canvas - Added bicubic interpolation and integration mask.

git-svn-id: https://subversion.assembla.com/svn/thunderk/paysages@393 b1fd45b6-86a6-48da-8261-f70d1f35bdcc

gui_qt/formterraincanvas.cpp

@@ -13,8 +13,8 @@ FormTerrainCanvas::FormTerrainCanvas(QWidget *parent, Layers* layers):
     addInputNoise(tr("Detail noise"), _definition->detail_noise);
     addInputDouble(tr("Detail noise height"), &_definition->detail_height_factor, 0.0, 20.0, 0.1, 1.0);
     addInputDouble(tr("Detail noise scaling"), &_definition->detail_scaling, 0.0, 20.0, 0.1, 1.0);
-    addInputEnum(tr("Mask shape"), &_definition->mask_mode, QStringList(tr("Square")) << tr("Circle"));
-    addInputDouble(tr("Mask smoothing"), &_definition->mask_smoothing, 0.0, 1.0, 0.01, 0.1);
+    addInputEnum(tr("Mask shape"), &_definition->mask.mode, QStringList(tr("Square")) << tr("Circle"));
+    addInputDouble(tr("Mask smoothing"), &_definition->mask.smoothing, 0.0, 1.0, 0.01, 0.1);
     
     revertConfig();
 }

lib_paysages/heightmap.c

@@ -1,4 +1,5 @@
 #include "heightmap.h"
+#include "tools.h"
 
 #include <stdlib.h>
 #include <string.h>
@@ -73,8 +74,26 @@ void heightmapChangeResolution(HeightMap* heightmap, int resolution_x, int resol
 
 double heightmapGetValue(HeightMap* heightmap, double x, double z)
 {
-    // TODO Bicubic interpolation
-    return heightmap->data[lround(z * (heightmap->resolution_z - 1)) * heightmap->resolution_x + lround(x * (heightmap->resolution_x - 1))];
+    int xmax = heightmap->resolution_x - 1;
+    int zmax = heightmap->resolution_z - 1;
+    int xlow = floor(x * xmax);
+    int zlow = floor(z * zmax);
+    double stencil[16];
+    int ix, iz, cx, cz;
+    
+    for (ix = xlow - 1; ix <= xlow + 2; ix++)
+    {
+        for (iz = zlow - 1; iz <= zlow + 2; iz++)
+        {
+            cx = ix < 0 ? 0 : ix;
+            cx = cx > xmax ? xmax : cx;
+            cz = iz < 0 ? 0 : iz;
+            cz = cz > zmax ? zmax : cz;
+            stencil[(iz - (zlow - 1)) * 4 + ix - (xlow - 1)] = heightmap->data[cz * heightmap->resolution_x + cx];
+        }
+    }
+    
+    return toolsBicubicInterpolate(stencil, x * xmax - (double)xlow, z * zmax - (double)zlow);
 }
 
 void heightmapBrushElevation(HeightMap* heightmap, HeightMapBrush* brush, double value)
@@ -82,7 +101,7 @@ void heightmapBrushElevation(HeightMap* heightmap, HeightMapBrush* brush, double
     int x, z;
     double dx, dz, distance;
     
-    // TODO Limit to brush radius
+    /* TODO Limit to brush radius */
     
     for (x = 0; x < heightmap->resolution_x; x++)
     {

lib_paysages/terraincanvas.c

@@ -19,8 +19,8 @@ TerrainCanvas* terrainCanvasCreate()
     result->detail_noise = noiseCreateGenerator();
     result->detail_height_factor = 0.1;
     result->detail_scaling = 1.0;
-    result->mask_mode = TERRAINCANVAS_MASKMODE_SQUARE;
-    result->mask_smoothing = 0.0;
+    result->mask.mode = INTEGRATIONMASK_MODE_CIRCLE;
+    result->mask.smoothing = 0.1;
     
     return result;
 }
@@ -41,8 +41,7 @@ void terrainCanvasCopy(TerrainCanvas* source, TerrainCanvas* destination)
     noiseCopy(source->detail_noise, destination->detail_noise);
     destination->detail_height_factor = source->detail_height_factor;
     destination->detail_scaling = source->detail_scaling;
-    destination->mask_mode = source->mask_mode;
-    destination->mask_smoothing = source->mask_smoothing;
+    destination->mask = source->mask;
 }
 
 void terrainCanvasValidate(TerrainCanvas* canvas)
@@ -82,8 +81,8 @@ void terrainCanvasSave(PackStream* stream, TerrainCanvas* canvas)
     noiseSaveGenerator(stream, canvas->detail_noise);
     packWriteDouble(stream, &canvas->detail_height_factor);
     packWriteDouble(stream, &canvas->detail_scaling);
-    packWriteInt(stream, &canvas->mask_mode);
-    packWriteDouble(stream, &canvas->mask_smoothing);
+    packWriteInt(stream, &canvas->mask.mode);
+    packWriteDouble(stream, &canvas->mask.smoothing);
 }
 
 void terrainCanvasLoad(PackStream* stream, TerrainCanvas* canvas)
@@ -99,8 +98,8 @@ void terrainCanvasLoad(PackStream* stream, TerrainCanvas* canvas)
     noiseLoadGenerator(stream, canvas->detail_noise);
     packReadDouble(stream, &canvas->detail_height_factor);
     packReadDouble(stream, &canvas->detail_scaling);
-    packReadInt(stream, &canvas->mask_mode);
-    packReadDouble(stream, &canvas->mask_smoothing);
+    packReadInt(stream, &canvas->mask.mode);
+    packReadDouble(stream, &canvas->mask.smoothing);
 }
 
 void terrainCanvasRevertToTerrain(TerrainCanvas* canvas, TerrainDefinition* terrain, int only_masked)
@@ -114,7 +113,39 @@ Vector3 terrainCanvasApply(TerrainCanvas* canvas, Vector3 location)
         location.x <= canvas->area.location_x + canvas->area.size_x &&
         location.z <= canvas->area.location_z + canvas->area.size_z)
     {
-        location.y = heightmapGetValue(&canvas->height_map, (location.x - canvas->area.location_x) / canvas->area.size_x, (location.z - canvas->area.location_z) / canvas->area.size_z);
+        double inside_x, inside_z;
+        double height, distance;
+        
+        /* Get height map displacement */
+        inside_x = (location.x - canvas->area.location_x) / canvas->area.size_x;
+        inside_z = (location.z - canvas->area.location_z) / canvas->area.size_z;
+        height = heightmapGetValue(&canvas->height_map, inside_x, inside_z);
+        
+        /* TODO Apply detail noise */
+        
+        /* Apply integration mask */
+        inside_x = (inside_x - 0.5) * 2.0;
+        inside_z = (inside_z - 0.5) * 2.0;
+        if (canvas->mask.mode == INTEGRATIONMASK_MODE_SQUARE)
+        {
+            inside_x = fabs(inside_x);
+            inside_z = fabs(inside_z);
+            distance = inside_x > inside_z ? inside_x : inside_z;
+        }
+        else
+        {
+            distance = sqrt(inside_x * inside_x + inside_z * inside_z);
+        }
+        if (distance <= 1.0 - canvas->mask.smoothing)
+        {
+            location.y = height;
+        }
+        else
+        {
+            double influence = (1.0 - distance) / canvas->mask.smoothing;
+            location.y = influence * height + (1.0 - influence) * location.y;
+        }
+        
     }
     return location;
 }

lib_paysages/terraincanvas.h

@@ -22,8 +22,14 @@ typedef struct
     double size_z;
 } GeoArea;
 
-#define TERRAINCANVAS_MASKMODE_SQUARE 0
-#define TERRAINCANVAS_MASKMODE_CIRCLE 1
+typedef struct
+{
+    int mode;
+    double smoothing;
+} IntegrationMask;
+
+#define INTEGRATIONMASK_MODE_SQUARE 0
+#define INTEGRATIONMASK_MODE_CIRCLE 1
 
 typedef struct
 {
@@ -34,8 +40,7 @@ typedef struct
     NoiseGenerator* detail_noise;
     double detail_height_factor;
     double detail_scaling;
-    int mask_mode;
-    double mask_smoothing;
+    IntegrationMask mask;
 } TerrainCanvas;
 
 TerrainCanvas* terrainCanvasCreate();