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fgdata/Shaders/HDR/ws30.frag
Stuart Buchanan dda21aeae1 HDR: W3.0 water shader - initial implementation
Implement a simple water shader for HDR.

Largely created from the non-HDR WS3.0 water shader,
but only generating a fragment normal.

Notes:
- Water color is a constant in the shader, and set by eye
  only.
- foam etc is not yet implemented.
- at very low altitudes the shader breaks down somewhat.
2024-02-24 17:09:51 +00:00

93 lines
2.8 KiB
GLSL

#version 330 core
in VS_OUT {
float flogz;
vec2 texcoord;
vec3 vertex_normal;
} fs_in;
uniform sampler2D landclass;
uniform sampler2DArray atlas;
uniform sampler2D perlin;
// Passed from VPBTechnique, not the Effect
uniform float fg_tileWidth;
uniform float fg_tileHeight;
uniform bool fg_photoScenery;
uniform vec4 fg_dimensionsArray[128];
uniform vec4 fg_ambientArray[128];
uniform vec4 fg_diffuseArray[128];
uniform vec4 fg_specularArray[128];
uniform vec4 fg_textureLookup1[128];
uniform vec4 fg_textureLookup2[128];
uniform mat4 fg_zUpTransform;
uniform vec3 fg_modelOffset;
uniform sampler2D coastline;
const float TERRAIN_METALLIC = 0.0;
const float TERRAIN_ROUGHNESS = 0.95;
const vec3 WATER_COLOR = vec3(0.1, 0.1, 0.3);
const float WATER_METALLIC = 0.0;
const float WATER_ROUGHNESS = 0.25;
// Procedurally generate a water normal for this fragment
vec3 generateWaterNormal(in vec2 texCoords);
// gbuffer_pack.glsl
void gbuffer_pack(vec3 normal, vec3 base_color, float metallic, float roughness,
float occlusion, vec3 emissive, uint mat_id);
// color.glsl
vec3 eotf_inverse_sRGB(vec3 srgb);
// logarithmic_depth.glsl
float logdepth_encode(float z);
void main()
{
vec3 texel;
vec4 specular = vec4(0.1, 0.1, 0.1, 1.0);
vec3 N = normalize(fs_in.vertex_normal);
float metallic = TERRAIN_METALLIC;
float roughness = TERRAIN_ROUGHNESS;
if (fg_photoScenery) {
texel = texture(landclass, vec2(fs_in.texcoord.s, 1.0 - fs_in.texcoord.t)).rgb;
} else {
// The Landclass for this particular fragment. This can be used to
// index into the atlas textures.
int lc = int(texture2D(landclass, fs_in.texcoord).g * 255.0 + 0.5);
bool water = (texture2D(landclass, fs_in.texcoord).z > 0.9) || (texture2D(coastline, fs_in.texcoord).b > 0.05);
uint tex1 = uint(fg_textureLookup1[lc].r * 255.0 + 0.5);
//color = ambientArray[lc] + diffuseArray[lc] * NdotL * gl_LightSource[0].diffuse;
specular = fg_specularArray[lc];
// Different textures have different dimensions.
vec2 atlas_dimensions = fg_dimensionsArray[lc].st;
vec2 atlas_scale = vec2(fg_tileWidth / atlas_dimensions.s, fg_tileHeight / atlas_dimensions.t );
vec2 st = atlas_scale * fs_in.texcoord;
// Rotate texture using the perlin texture as a mask to reduce tiling
if (step(0.5, texture(perlin, atlas_scale * fs_in.texcoord / 8.0).r) == 1.0) {
st = vec2(atlas_scale.s * fs_in.texcoord.t, atlas_scale.t * fs_in.texcoord);
}
if (step(0.5, texture(perlin, - atlas_scale * fs_in.texcoord / 16.0).r) == 1.0) {
st = -st;
}
texel = texture(atlas, vec3(st, tex1)).rgb;
if (water) {
N = generateWaterNormal(fs_in.texcoord);
texel = WATER_COLOR;
roughness = WATER_ROUGHNESS;
metallic = WATER_METALLIC;
}
}
vec3 color = eotf_inverse_sRGB(texel);
gbuffer_pack(N, color, metallic, roughness, 1.0, vec3(0.0), 3u);
gl_FragDepth = logdepth_encode(fs_in.flogz);
}