Added bounding box system, with camera support

src/rendering/camera.c

@@ -5,6 +5,7 @@
 #include "render.h"
 #include "scenery.h"
 #include "tools.h"
+#include "tools/boundingbox.h"
 
 struct CameraDefinition
 {
@@ -361,58 +362,49 @@ Vector3 cameraUnproject(CameraDefinition* camera, Vector3 point)
     renderPushQuad(&v1, &v2, &v3, &v4);
 }*/
 
-static inline void _updateBox(Vector3* point, double* xmin, double* xmax, double* ymin, double* ymax, double* zmax)
-{
-    *xmin = (*xmin < point->x) ? *xmin : point->x;
-    *ymin = (*ymin < point->y) ? *ymin : point->y;
-
-    *xmax = (*xmax > point->x) ? *xmax : point->x;
-    *ymax = (*ymax > point->y) ? *ymax : point->y;
-    *zmax = (*zmax > point->z) ? *zmax : point->z;
-}
-
 int cameraIsBoxInView(CameraDefinition* camera, Vector3 center, double xsize, double ysize, double zsize)
 {
-    Vector3 projected;
+    BoundingBox box;
-    double xmin, xmax, ymin, ymax, zmax;
 
-    center.x -= xsize / 2.0;
+    boundingBoxReset(&box);
-    center.y -= ysize / 2.0;
-    center.z -= zsize / 2.0;
-    projected = cameraProject(camera, center);
-    xmin = xmax = projected.x;
-    ymin = ymax = projected.y;
-    zmax = projected.z;
 
-    center.x += xsize;
+    boundingBoxPushPoint(&box, v3Add(center, v3(-xsize, -ysize, -zsize)));
-    projected = cameraProject(camera, center);
+    boundingBoxPushPoint(&box, v3Add(center, v3(xsize, ysize, zsize)));
-    _updateBox(&projected, &xmin, &xmax, &ymin, &ymax, &zmax);
 
-    center.z += zsize;
+    return cameraIsUnprojectedBoxInView(camera, &box);
-    projected = cameraProject(camera, center);
+}
-    _updateBox(&projected, &xmin, &xmax, &ymin, &ymax, &zmax);
 
-    center.x -= xsize;
+int cameraIsUnprojectedBoxInView(CameraDefinition* camera, BoundingBox* box)
-    projected = cameraProject(camera, center);
+{
-    _updateBox(&projected, &xmin, &xmax, &ymin, &ymax, &zmax);
+    BoundingBox projected;
 
-    center.y += ysize;
+    boundingBoxReset(&projected);
-    projected = cameraProject(camera, center);
-    _updateBox(&projected, &xmin, &xmax, &ymin, &ymax, &zmax);
 
-    center.x += xsize;
+    boundingBoxPushPoint(&projected, cameraProject(camera, v3(box->xmin, box->ymin, box->zmin)));
-    projected = cameraProject(camera, center);
+    boundingBoxPushPoint(&projected, cameraProject(camera, v3(box->xmax, box->ymin, box->zmin)));
-    _updateBox(&projected, &xmin, &xmax, &ymin, &ymax, &zmax);
+    boundingBoxPushPoint(&projected, cameraProject(camera, v3(box->xmin, box->ymax, box->zmin)));
+    boundingBoxPushPoint(&projected, cameraProject(camera, v3(box->xmax, box->ymax, box->zmin)));
+    boundingBoxPushPoint(&projected, cameraProject(camera, v3(box->xmin, box->ymin, box->zmax)));
+    boundingBoxPushPoint(&projected, cameraProject(camera, v3(box->xmax, box->ymin, box->zmax)));
+    boundingBoxPushPoint(&projected, cameraProject(camera, v3(box->xmin, box->ymax, box->zmax)));
+    boundingBoxPushPoint(&projected, cameraProject(camera, v3(box->xmax, box->ymax, box->zmax)));
 
-    center.z -= zsize;
+    return cameraIsProjectedBoxInView(camera, &projected);
-    projected = cameraProject(camera, center);
+}
-    _updateBox(&projected, &xmin, &xmax, &ymin, &ymax, &zmax);
 
-    center.x -= xsize;
+int cameraIsProjectedBoxInView(CameraDefinition* camera, BoundingBox* box)
-    projected = cameraProject(camera, center);
+{
-    _updateBox(&projected, &xmin, &xmax, &ymin, &ymax, &zmax);
+    if (box->xmin <= camera->width && box->xmax >= 0.0 && box->ymin <= camera->height && box->ymax >= 0.0 && box->zmax >= camera->perspective.znear)
+    {
+        double dx = box->xmax - box->xmin;
+        double dy = box->ymax - box->ymin;
 
-    return xmin <= camera->width && xmax >= 0.0 && ymin <= camera->height && ymax >= 0.0 && zmax >= camera->perspective.znear;
+        return (int)ceil(dx) * (int)ceil(dy);
+    }
+    else
+    {
+        return 0;
+    }
 }
 
 int cameraTransitionToAnother(CameraDefinition* current, CameraDefinition* wanted, double factor)

src/rendering/camera.h

@@ -3,6 +3,7 @@
 
 #include "tools/pack.h"
 #include "tools/euclid.h"
+#include "tools/boundingbox.h"
 
 #ifdef __cplusplus
 extern "C"
@@ -57,6 +58,8 @@ Vector3 cameraProject(CameraDefinition* camera, Vector3 point);
 Vector3 cameraUnproject(CameraDefinition* camera, Vector3 point);
 /*void cameraPushOverlay(CameraDefinition* camera, Color col, f_RenderFragmentCallback callback);*/
 int cameraIsBoxInView(CameraDefinition* camera, Vector3 center, double xsize, double ysize, double zsize);
+int cameraIsUnprojectedBoxInView(CameraDefinition* camera, BoundingBox* box);
+int cameraIsProjectedBoxInView(CameraDefinition* camera, BoundingBox* box);
 
 int cameraTransitionToAnother(CameraDefinition* current, CameraDefinition* wanted, double factor);
 

src/rendering/tools/boundingbox.c

@@ -0,0 +1,41 @@
+#include "boundingbox.h"
+
+void boundingBoxReset(BoundingBox* box)
+{
+    box->empty = 1;
+    box->xmin = 10000000000.0;
+    box->xmax = -10000000000.0;
+    box->ymin = 10000000000.0;
+    box->ymax = -10000000000.0;
+    box->zmin = 10000000000.0;
+    box->zmax = -10000000000.0;
+}
+
+void boundingBoxPushPoint(BoundingBox* box, Vector3 point)
+{
+    box->empty = 0;
+    if (point.x < box->xmin)
+    {
+        box->xmin = point.x;
+    }
+    if (point.x > box->xmax)
+    {
+        box->xmax = point.x;
+    }
+    if (point.y < box->ymin)
+    {
+        box->ymin = point.y;
+    }
+    if (point.y > box->ymax)
+    {
+        box->ymax = point.y;
+    }
+    if (point.z < box->zmin)
+    {
+        box->zmin = point.z;
+    }
+    if (point.z > box->zmax)
+    {
+        box->zmax = point.z;
+    }
+}

src/rendering/tools/boundingbox.h

@@ -0,0 +1,28 @@
+#ifndef _RENDERING_TOOLS_BOUNDINGBOX_H_
+#define _RENDERING_TOOLS_BOUNDINGBOX_H_
+
+#include "euclid.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct
+{
+    int empty;
+    double xmin;
+    double xmax;
+    double ymin;
+    double ymax;
+    double zmin;
+    double zmax;
+} BoundingBox;
+
+void boundingBoxReset(BoundingBox* box);
+void boundingBoxPushPoint(BoundingBox* box, Vector3 point);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif