Welcome to Fractal Forums

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

uniform sampler2D myTexture; file[test.png]
#TexParameter myTexture GL_TEXTURE_MAX_LEVEL 1000
#TexParameter myTexture GL_TEXTURE_WRAP_S GL_REPEAT
#TexParameter myTexture GL_TEXTURE_WRAP_T GL_REPEAT
#TexParameter myTexture GL_TEXTURE_MAG_FILTER GL_LINEAR
#TexParameter myTexture GL_TEXTURE_MIN_FILTER GL_LINEAR_MIPMAP_LINEAR

uniform sampler2D myTexture; file[test.png]
#TexParameter myTexture GL_TEXTURE_MIN_FILTER GL_LINEAR

grep dFd Fragmentarium/Examples/*/*
....
result:
BufferShader-1.0.1.frag:  vec2 pixelsiz=vec2(dFdx(pos.x),dFdy(pos.y));
DepthBufferShader.frag:   // vec3 n = normalize(cross( dFdx(worldPos), dFdy(worldPos) ));
ZBufferShader.frag:       vec3 n = normalize(cross( dFdx(worldPos), dFdy(worldPos) ));

0(434) : warning C7548: '<<' requires "#extension GL_EXT_gpu_shader4 : enable" before use
0(434) : warning C7548: '^' requires "#extension GL_EXT_gpu_shader4 : enable" before use

/* The state must be seeded so that it is not everywhere zero. */
ivec2 seed;

float xorshift128plus(void) {
	ivec2 s = seed;
	seed.x = s.y;
	s.x ^= s.x << 23; // a
	s.x ^= s.x >> 17; // b
	s.x ^= s.y ^ (s.y >> 26); // c
	seed.y = s.x;
	return 1.0 / (float(s.x) + float(s.y));
}

float rand(vec2 co){
	// implementation found at: lumina.sourceforge.net/Tutorials/Noise.html
	// return fract(sin(dot(co.xy ,vec2(12.9898,78.233))) * 43758.5453);
seed = ivec2(43758,5453);
return xorshift128plus();
}

#extension GL_ARB_shader_bit_encoding : enable
#extension GL_EXT_gpu_shader4 : enable
#extension GL_ARB_gpu_shader5 : enable
#include "2D.frag"

uint wang_hash(uint seed)
{
	seed = (seed ^ 61u) ^ (seed >> 16u);
	seed *= 9u;
	seed = seed ^ (seed >> 4u);
	seed *= 0x27d4eb2du;
	seed = seed ^ (seed >> 15u);
	return seed ;
}


// Wrapper for getting from float to ints. This certainly looses precision. I imagine we could do better here.
float wang_hash_fp(vec2 pos)
{
	uint ix = floatBitsToUint(pos.x);
	uint iy = floatBitsToUint(pos.y);
        // I use two hash calls to untangle pos.x and pos.y
	return float(wang_hash(wang_hash(ix)+iy)) / 4294967296.0;
}

// old 'rand1' for comparison.
float rand1(vec2 co){
	return fract(sin(dot(co.xy ,vec2(12.9898,78.233))) * 43758.5453);
}


vec3 color(vec2 z)  {
	// return rand1(z) < 0.5 ? vec3(1.0) : vec3(0.0);
 	return wang_hash_fp(z) < 0.5 ? vec3(1.0) : vec3(0.0);
}

float rand(vec3 co){// implementation found at: lumina.sourceforge.net/Tutorials/Noise.html
	return fract(sin(dot(co*0.123,vec3(12.9898,78.233,112.166))) * 43758.5453);
}

float rand(vec3 co){// implementation found at: lumina.sourceforge.net/Tutorials/Noise.html
	return fract(sin(dot(co,vec3(12.9898,78.233,112.166))) * 43758.5453);
}

float wang_hash_fp(vec3 pos)
{
	uint ix = floatBitsToUint(pos.x);
	uint iy = floatBitsToUint(pos.y);
	uint iz = floatBitsToUint(pos.z);
        // I use three hash calls to untangle pos.xyz
	return float(wang_hash(wang_hash(wang_hash(ix)+iy)+iz) / 4294967296.0;
}

/// in a frag this should create a mipmapped texture with 1000 levels
uniform sampler2D myTexture; file[test.png]
#TexParameter myTexture GL_TEXTURE_MAX_LEVEL 1000
#TexParameter myTexture GL_TEXTURE_WRAP_S GL_REPEAT
#TexParameter myTexture GL_TEXTURE_WRAP_T GL_REPEAT
#TexParameter myTexture GL_TEXTURE_MAG_FILTER GL_LINEAR
#TexParameter myTexture GL_TEXTURE_MIN_FILTER GL_LINEAR_MIPMAP_LINEAR

int iRay=subframe

//random seed and generator
vec2 randv2=fract(cos((gl_FragCoord.xy+gl_FragCoord.yx*vec2(1000.0,1000.0))+vec2(time)*10.0+vec2(iRay,iRay))*10000.0);
vec2 rand2(){// implementation derived from one found at: lumina.sourceforge.net/Tutorials/Noise.html
	randv2+=vec2(1.0,1.0);
	return vec2(fract(sin(dot(randv2.xy ,vec2(12.9898,78.233))) * 43758.5453),
		fract(cos(dot(randv2.xy ,vec2(4.898,7.23))) * 23421.631));
}

vec2 seed = viewCoord*(float(subframe)+1.0);

vec2 rand2() {

	seed+=vec2(-1,1);
	return rand2(seed);
};

#extension GL_ARB_shader_bit_encoding : enable
#extension GL_EXT_gpu_shader4 : enable
#extension GL_ARB_gpu_shader5 : enable

uint wang_hash(uint seed)
{
        seed = (seed ^ 61u) ^ (seed >> 16u);
        seed *= 9u;
        seed = seed ^ (seed >> 4u);
        seed *= 0x27d4eb2du;
        seed = seed ^ (seed >> 15u);
        return seed ;
}

// Wrapper for getting from float to ints. This certainly looses precision. I imagine we could do better here.
float wang_hash_fp(float v)
{
        uint ix = floatBitsToUint(v);
        return float(wang_hash(ix)) / 4294967296.0;
}

float rand(vec2 co){
        // implementation found at: lumina.sourceforge.net/Tutorials/Noise.html
        // modified for seeding with wang hash function provided by Syntopia
        return fract(sin(dot(co.xy ,vec2(wang_hash_fp(co.x),wang_hash_fp(co.y)))) * 43758.5453);
}

float rand(vec3 co){
        // implementation found at: lumina.sourceforge.net/Tutorials/Noise.html
        // modified for seeding with wang hash function provided by Syntopia
        return fract(sin(dot(co,vec3(wang_hash_fp(co.x),wang_hash_fp(co.y),wang_hash_fp(co.z)))) * 43758.5453);
}

//random seed and generator
vec2 randv2=fract(cos((gl_FragCoord.xy+gl_FragCoord.yx*vec2(1000.0,1000.0))+vec2(time)*10.0+vec2(iRay,iRay))*10000.0);
vec2 rand2(){// implementation derived from one found at: lumina.sourceforge.net/Tutorials/Noise.html
        randv2+=vec2(1.0,1.0);
        return vec2(fract(sin(dot(randv2.xy ,vec2(wang_hash_fp(randv2.x),wang_hash_fp(randv2.y)))) * 43758.5453),
                fract(cos(dot(randv2.xy ,vec2(wang_hash_fp(randv2.x),wang_hash_fp(randv2.y)))) * 23421.631));
}

vec2 seed = viewCoord*(float(subframe)+1.0);

vec2 rand2() {

	seed+=vec2(-1,1);
	return vec2(wang_hash_fp(seed.x),wang_hash_fp(seed.y));
};

vec2 seed = viewCoord*(float(subframe)+1.0);

vec2 rand2() {

	seed+=vec2(-1,1);
	return vec2(wang_hash_fp(seed.x),wang_hash_fp(seed.y));
};

vec2 seed = viewCoord*(float(subframe)+1.0);

vec2 rand2() {

	seed+=vec2(-1,1);
	return rand2(seed);
};

//random seed and generator
vec2 randv2=fract(cos((gl_FragCoord.xy+gl_FragCoord.yx*vec2(1000.0,1000.0))+vec2(time)*10.0+vec2(iRay,iRay))*10000.0);
vec2 rand2(){// implementation derived from one found at: lumina.sourceforge.net/Tutorials/Noise.html
        randv2+=vec2(1.0,1.0);
        return vec2(fract(sin(dot(randv2.xy ,vec2(wang_hash_fp(randv2.x),wang_hash_fp(randv2.y)))) * 43758.5453),
                fract(cos(dot(randv2.xy ,vec2(wang_hash_fp(randv2.x),wang_hash_fp(randv2.y)))) * 23421.631));
}

vec2 seed = viewCoord*(float(subframe)+1.0);

vec2 rand2() {

	seed+=vec2(-1,1);
	return vec2(wang_hash_fp(seed.x),wang_hash_fp(seed.y));
};

vec2 seed = viewCoord*(float(subframe)+1.0);

vec2 rand2n() {
	seed+=vec2(wang_hash_fp(seed.x),wang_hash_fp(seed.y));
	return rand2(seed);
};

vec2 rand2(vec2 pos){
	uint ix = floatBitsToUint(pos.x);
	uint iy = floatBitsToUint(pos.y);
	return vec2((wang_hash(wang_hash(ix)+iy)) / 4294967296.0, (wang_hash(wang_hash(iy)+ix)) / 4294967296.0);
}