FPMColor MatrixTransformer(Coordinates where, RenderFlags flags, void *context)
{
MatrixTransformerContext *cx = context;
Vector v = CoordsGetVector(where);
v = OOVectorMultiplyMatrix(v, cx->transform);
where = MakeCoordsVector(v);
return cx->source(where, flags, cx->sourceContext);
}
FPMColor CosineBlurFilter(Coordinates where, RenderFlags flags, void *context)
{
Vector outV = CoordsGetVector(where);
FPMColor colorAccum = kFPMColorClear;
float weightAccum = 0.0f;
SampleFace(outV, make_vector(0, 0, 1), make_vector(0, 1, 0), make_vector( 1, 0, 0), context, flags, &colorAccum, &weightAccum);
SampleFace(outV, make_vector(0, 0, 1), make_vector(0, 1, 0), make_vector(-1, 0, 0), context, flags, &colorAccum, &weightAccum);
SampleFace(outV, make_vector(1, 0, 0), make_vector(0, 0, 1), make_vector(0, 1, 0), context, flags, &colorAccum, &weightAccum);
SampleFace(outV, make_vector(1, 0, 0), make_vector(0, 0, 1), make_vector(0, -1, 0), context, flags, &colorAccum, &weightAccum);
SampleFace(outV, make_vector(0, 1, 0), make_vector(1, 0, 0), make_vector(0, 0, 1), context, flags, &colorAccum, &weightAccum);
SampleFace(outV, make_vector(0, 1, 0), make_vector(1, 0, 0), make_vector(0, 0, -1), context, flags, &colorAccum, &weightAccum);
weightAccum = 1.0f / weightAccum;
colorAccum.r *= weightAccum;
colorAccum.g *= weightAccum;
colorAccum.b *= weightAccum;
colorAccum.a = 1.0f;
return colorAccum;
}
static FPMColor ReadCube(Coordinates where, RenderFlags flags, void *context)
{
assert(context != NULL);
ReadCubeContext *cx = context;
// The largest coordinate component determines which face we’re looking at.
Vector coords = CoordsGetVector(where);
float ax = fabsf(coords.x);
float ay = fabsf(coords.y);
float az = fabsf(coords.z);
FPMPoint faceOffset;
float x, y;
assert(ax != 0.0f || ay != 0.0f || az != 0.0f);
if (ax > ay && ax > az)
{
x = coords.z / ax;
y = -coords.y / ax;
if (0 < coords.x)
{
x = -x;
faceOffset = cx->pxPos;
}
else
{
faceOffset = cx->nxPos;
}
}
else if (ay > ax && ay > az)
{
x = coords.x / ay;
y = coords.z / ay;
if (0 < coords.y)
{
faceOffset = cx->pyPos;
}
else
{
y = -y;
faceOffset = cx->nyPos;
}
}
else
{
x = coords.x / az;
y = -coords.y / az;
if (0 < coords.z)
{
faceOffset = cx->pzPos;
}
else
{
x = -x;
faceOffset = cx->nzPos;
}
}
x = x * cx->halfWidth + cx->halfWidth;
y = y * cx->halfHeight + cx->halfHeight;
#if 0
if (x < 0.0 || x > (cx->halfWidth * 2.0 - 1.0)) printf("x: %g (width: %g)\n", x, cx->halfWidth * 2.0);
if (y < 0.0 || y > (cx->halfHeight * 2.0 - 1.0)) printf("y: %g (height: %g)\n", y, cx->halfHeight * 2.0);
#endif
if (1)//(1 <= x && x <= cx->maxX && 1 <= y && y <= cx->maxY)
{
FPMColor result = FPMSampleLinearClamp(cx->pm, x + faceOffset.x, y + faceOffset.y);
if (result.a < 0.95)
{
result = (FPMColor){ 10, 0, 0, 1 };
printf("%g, %g\n", x, y);
}
return result;
}
else
{
// Deal with nasty edge cases.
return ReadCubeEdge(cx, x, y, coords);
}
}
