image processing basics

[xoxos]

If your compiler is a 32-bit compiler, it would likely not be able to generate data much more than 1GB or so in a single allocation (you're breaking between 256MB and 512MB, which might also be a 32-bit compiler limit).

quite right, i was only looking at the indexing not the footprint

i'm going to have to think about what you've said as i may be going about this in the wrong fashion. my implementation seems very elementary to me without any optimisations between octaves. i'll paste it below in case you feel like (lol) poring through someone else's code..

simplex noise didn't sink in at all. i'd imagine a year of familiarisation with 2,3d thinking may change that. fortunately, since this is more of an exercise, the only thing i'd really gain by speed improvements is the time spent in development. ty again.

	for (y = 0; y < 2048; y++) {
		fla = (float)y / 651.580337f;	//	2047/pi
		fy = cos(fla) * hfbase;	fr = -sin(fla) * hfbase;
		for (x = 0; x < 4096; x++) {
			hf[hu][x][y] = 0;
			flo = (float)x / 651.7394919613114f + adjlong;	//	4095/tau
			fx = cos(flo) * fr;	fz = sin(flo) * fr;
			//	fx, fy, and fz mapped to sphere of radius 1 with center at origin if hfbase is removed from above

			float sum = 0.f;
			for (j = 0; j < woct; j++) {
				dx = fx * pp2[j];	dy = fy * pp2[j];	dz = fz * pp2[j];
				if (dx < 0.f) dx += 131072.f;	ix = (int)dx;	dx -= ix;	x1 = ix & 0x1f;
				if (dy < 0.f) dy += 131072.f;	iy = (int)dy;	dy -= iy;	y1 = iy & 0x1f;
				if (dz < 0.f) dz += 131072.f;	iz = (int)dz;	dz -= iz;	z1 = iz & 0x1f;

				x0 = x1 - 1;	x2 = x1 + 1;	x3 = x1 + 2;
				y0 = y1 - 1;	y2 = y1 + 1;	y3 = y1 + 2;
				z0 = z1 - 1;	z2 = z1 + 1;	z3 = z1 + 2;
				x0 &= 0x1f;	x2 &= 0x1f;	x3 &= 0x1f;
				y0 &= 0x1f;	y2 &= 0x1f;	y3 &= 0x1f;
				z0 &= 0x1f;	z2 &= 0x1f;	z3 &= 0x1f;

				p0 = tricint(dx, perlin[x0][y0][z0], perlin[x1][y0][z0], perlin[x2][y0][z0], perlin[x3][y0][z0]);
				p1 = tricint(dx, perlin[x0][y1][z0], perlin[x1][y1][z0], perlin[x2][y1][z0], perlin[x3][y1][z0]);
				p2 = tricint(dx, perlin[x0][y2][z0], perlin[x1][y2][z0], perlin[x2][y2][z0], perlin[x3][y2][z0]);
				p3 = tricint(dx, perlin[x0][y3][z0], perlin[x1][y3][z0], perlin[x2][y3][z0], perlin[x3][y3][z0]);
				pa = tricint(dy, p0, p1, p2, p3);

				p0 = tricint(dx, perlin[x0][y0][z1], perlin[x1][y0][z1], perlin[x2][y0][z1], perlin[x3][y0][z1]);
				p1 = tricint(dx, perlin[x0][y1][z1], perlin[x1][y1][z1], perlin[x2][y1][z1], perlin[x3][y1][z1]);
				p2 = tricint(dx, perlin[x0][y2][z1], perlin[x1][y2][z1], perlin[x2][y2][z1], perlin[x3][y2][z1]);
				p3 = tricint(dx, perlin[x0][y3][z1], perlin[x1][y3][z1], perlin[x2][y3][z1], perlin[x3][y3][z1]);
				pb = tricint(dy, p0, p1, p2, p3);

				p0 = tricint(dx, perlin[x0][y0][z2], perlin[x1][y0][z2], perlin[x2][y0][z2], perlin[x3][y0][z2]);
				p1 = tricint(dx, perlin[x0][y1][z2], perlin[x1][y1][z2], perlin[x2][y1][z2], perlin[x3][y1][z2]);
				p2 = tricint(dx, perlin[x0][y2][z2], perlin[x1][y2][z2], perlin[x2][y2][z2], perlin[x3][y2][z2]);
				p3 = tricint(dx, perlin[x0][y3][z2], perlin[x1][y3][z2], perlin[x2][y3][z2], perlin[x3][y3][z2]);
				pc = tricint(dy, p0, p1, p2, p3);

				p0 = tricint(dx, perlin[x0][y0][z3], perlin[x1][y0][z3], perlin[x2][y0][z3], perlin[x3][y0][z3]);
				p1 = tricint(dx, perlin[x0][y1][z3], perlin[x1][y1][z3], perlin[x2][y1][z3], perlin[x3][y1][z3]);
				p2 = tricint(dx, perlin[x0][y2][z3], perlin[x1][y2][z3], perlin[x2][y2][z3], perlin[x3][y2][z3]);
				p3 = tricint(dx, perlin[x0][y3][z3], perlin[x1][y3][z3], perlin[x2][y3][z3], perlin[x3][y3][z3]);
				pd = tricint(dy, p0, p1, p2, p3);

				o = tricint(dz, pa, pb, pc, pd);
				if (j < 2) {
					sum += o * pn2[j + 1];
				}
				else {
					if (o > 32767.5f) o = 65535.f - o;
					sum += o * pn2[j];
				}
			}
			sum *= sumdiv;
			i = (int)sum;
			if (i < 0) i = 0;
			else if (i > 65535) i = 65535;
			hf[hu][x][y] = i >> 8;
	}	}

wow, that gradient b/g makes code a trip :p

(realsiing that i ought to add latitudinal rotation as well as it only needs to be performed for each pixel, not each octave..)