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uniform sampler2D baseTexture;
uniform sampler2D normalTexture;
uniform sampler2D textureFlags;
uniform vec4 skyBgColor;
uniform float fogDistance;
uniform vec3 eyePosition;
varying vec3 vPosition;
varying vec3 worldPosition;
varying vec3 eyeVec;
varying vec3 tsEyeVec;
varying vec3 lightVec;
varying vec3 tsLightVec;
bool normalTexturePresent = false;
bool texTileableHorizontal = false;
bool texTileableVertical = false;
bool texSeamless = false;
const float e = 2.718281828459;
const float BS = 10.0;
const float fogStart = 0.4;
const float fogShadingParameter = 1 / ( 1 - fogStart);
#ifdef ENABLE_TONE_MAPPING
/* Hable's UC2 Tone mapping parameters
A = 0.22;
B = 0.30;
C = 0.10;
D = 0.20;
E = 0.01;
F = 0.30;
W = 11.2;
equation used: ((x * (A * x + C * B) + D * E) / (x * (A * x + B) + D * F)) - E / F
*/
vec3 uncharted2Tonemap(vec3 x)
{
return ((x * (0.22 * x + 0.03) + 0.002) / (x * (0.22 * x + 0.3) + 0.06)) - 0.03334;
}
vec4 applyToneMapping(vec4 color)
{
color = vec4(pow(color.rgb, vec3(2.2)), color.a);
const float gamma = 1.6;
const float exposureBias = 5.5;
color.rgb = uncharted2Tonemap(exposureBias * color.rgb);
// Precalculated white_scale from
//vec3 whiteScale = 1.0 / uncharted2Tonemap(vec3(W));
vec3 whiteScale = vec3(1.036015346);
color.rgb *= whiteScale;
return vec4(pow(color.rgb, vec3(1.0 / gamma)), color.a);
}
#endif
void get_texture_flags()
{
vec4 flags = texture2D(textureFlags, vec2(0.0, 0.0));
if (flags.r > 0.5) {
normalTexturePresent = true;
}
if (flags.g > 0.5) {
texTileableHorizontal = true;
}
if (flags.b > 0.5) {
texTileableVertical = true;
}
if (texTileableHorizontal && texTileableVertical) {
texSeamless = true;
}
}
float intensity(vec3 color)
{
return (color.r + color.g + color.b) / 3.0;
}
float get_rgb_height(vec2 uv)
{
return intensity(texture2D(baseTexture,uv).rgb);
}
vec4 get_normal_map(vec2 uv)
{
vec4 bump = texture2D(normalTexture, uv).rgba;
bump.xyz = normalize(bump.xyz * 2.0 -1.0);
bump.y = -bump.y;
return bump;
}
void main(void)
{
vec3 color;
vec4 bump;
vec2 uv = gl_TexCoord[0].st;
bool use_normalmap = false;
get_texture_flags();
#ifdef ENABLE_PARALLAX_OCCLUSION
if (normalTexturePresent) {
vec3 tsEye = normalize(tsEyeVec);
float height = PARALLAX_OCCLUSION_SCALE * texture2D(normalTexture, uv).a - PARALLAX_OCCLUSION_BIAS;
uv = uv + texture2D(normalTexture, uv).z * height * vec2(tsEye.x,-tsEye.y);
}
#endif
#ifdef USE_NORMALMAPS
if (normalTexturePresent) {
bump = get_normal_map(uv);
use_normalmap = true;
}
#endif
if (GENERATE_NORMALMAPS == 1 && use_normalmap == false) {
float tl = get_rgb_height (vec2(uv.x-SAMPLE_STEP,uv.y+SAMPLE_STEP));
float t = get_rgb_height (vec2(uv.x-SAMPLE_STEP,uv.y-SAMPLE_STEP));
float tr = get_rgb_height (vec2(uv.x+SAMPLE_STEP,uv.y+SAMPLE_STEP));
float r = get_rgb_height (vec2(uv.x+SAMPLE_STEP,uv.y));
float br = get_rgb_height (vec2(uv.x+SAMPLE_STEP,uv.y-SAMPLE_STEP));
float b = get_rgb_height (vec2(uv.x,uv.y-SAMPLE_STEP));
float bl = get_rgb_height (vec2(uv.x-SAMPLE_STEP,uv.y-SAMPLE_STEP));
float l = get_rgb_height (vec2(uv.x-SAMPLE_STEP,uv.y));
float dX = (tr + 2.0 * r + br) - (tl + 2.0 * l + bl);
float dY = (bl + 2.0 * b + br) - (tl + 2.0 * t + tr);
bump = vec4 (normalize(vec3 (dX, -dY, NORMALMAPS_STRENGTH)),1.0);
use_normalmap = true;
}
vec4 base = texture2D(baseTexture, uv).rgba;
#ifdef ENABLE_BUMPMAPPING
if (use_normalmap) {
vec3 L = normalize(lightVec);
vec3 E = normalize(eyeVec);
float specular = pow(clamp(dot(reflect(L, bump.xyz), E), 0.0, 1.0),0.5);
float diffuse = dot(E,bump.xyz);
/* Mathematic optimization
* Original: color = 0.05*base.rgb + diffuse*base.rgb + 0.2*specular*base.rgb;
* This optimization save 2 multiplications (orig: 4 multiplications + 3 additions
* end: 2 multiplications + 3 additions)
*/
color = (0.05 + diffuse + 0.2 * specular) * base.rgb;
} else {
color = base.rgb;
}
#else
color = base.rgb;
#endif
vec4 col = vec4(color.rgb * gl_Color.rgb, 1.0);
#ifdef ENABLE_TONE_MAPPING
col = applyToneMapping(col);
#endif
if (fogDistance != 0.0) {
// Due to a bug in some (older ?) graphics stacks (possibly in the glsl compiler ?),
// the fog will only be rendered correctly if the last operation before the
// clamp() is an addition. Else, the clamp() seems to be ignored.
// E.g. the following won't work:
// float clarity = clamp(fogShadingParameter
// * (fogDistance - length(eyeVec)) / fogDistance), 0.0, 1.0);
// As additions usually come for free following a multiplication, the new formula
// should be more efficient as well.
// Note: clarity = (1 - fogginess)
float clarity = clamp(fogShadingParameter
- fogShadingParameter * length(eyeVec) / fogDistance, 0.0, 1.0);
col = mix(skyBgColor, col, clarity);
}
col = vec4(col.rgb, base.a);
gl_FragColor = col;
}
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