terravisor/shaders/tessellation_eval.glsl

137 lines
3.7 KiB
GLSL

#version 450 core
layout(quads, fractional_even_spacing, cw) in;
in TC_OUT {
vec3 position;
vec2 texCoord;
} te_in[];
layout(location = 0) uniform mat4 M;
layout(std140, binding = 0) uniform SceneUniforms
{
mat4 PV; //camera projection * view matrix
vec4 eye_w; //world-space eye position
};
out vec3 fragPosition;
layout(binding = 0) uniform sampler2D heightTexture;
uniform float displacementScale = 0.1;
void main() {
// Interpolate texture coordinates
vec2 texCoord = mix(
mix(te_in[0].texCoord, te_in[1].texCoord, gl_TessCoord[0]),
mix(te_in[3].texCoord, te_in[2].texCoord, gl_TessCoord[0]),
gl_TessCoord[1]
);
// Interpolate the original position
vec3 position = mix(
mix(te_in[0].position, te_in[1].position, gl_TessCoord[0]),
mix(te_in[3].position, te_in[2].position, gl_TessCoord[0]),
gl_TessCoord[1]
);
fragPosition = (PV*M*vec4(position, 1.0)).xyz;
gl_Position = PV*M*vec4(position, 1.0f);
}
// layout(quads, equal_spacing, ccw) in; // Define the type of patch (e.g., quads)
// in vec2 tcs_uv[];
// layout(binding = 0) uniform sampler2D heightTexture;
// layout(location = 0) uniform mat4 M;
// layout(std140, binding = 0) uniform SceneUniforms
// {
// mat4 PV; //camera projection * view matrix
// vec4 eye_w; //world-space eye position
// };
// in VertexData {
// vec2 tex_coord;
// } inData[];
// out vec3 frag_position; // Ensure this matches the input in fragment.glsl
// out VertexData {
// vec2 tex_coord;
// } outData;
// float getHeight(vec2 uv) {
// return texture(heightTexture, uv).r;
// }
// void main()
// {
// const float u = gl_TessCoord[0];
// const float v = gl_TessCoord[1];
// vec2 tess_coord = gl_TessCoord.xy;
// vec2 base_uv = mix(tcs_uv[0], tcs_uv[1], tess_coord.x);
// base_uv = mix(base_uv, mix(tcs_uv[3], tcs_uv[2], tess_coord.x), tess_coord.y);
// vec4 htex = texture(heightTexture, base_uv);
// const vec4 p0 = PV*M*gl_in[0].gl_Position;
// const vec4 p1 = PV*M*gl_in[1].gl_Position;
// const vec4 p2 = PV*M*gl_in[2].gl_Position;
// const vec4 p3 = PV*M*gl_in[3].gl_Position;
// vec4 a = mix(p0, p1, u);
// vec4 b = mix(p3, p2, u);
// vec4 c = mix(a, b, v);
// c.y = htex.r * 0.5f;
// float eps = 0.0002;
// float hCenter = getHeight(base_uv);
// float hRight = getHeight(base_uv + vec2(eps, 0.0));
// float hLeft = getHeight(base_uv - vec2(eps, 0.0));
// float hUp = getHeight(base_uv + vec2(0.0, eps));
// float hDown = getHeight(base_uv - vec2(0.0, eps));
// vec3 tangentX = normalize(vec3(0.002, hRight - hLeft, 0.0));
// vec3 tangentZ = normalize(vec3(0.0, hUp - hDown, 0.002));
// vec3 d0 = gl_in[0].gl_Position.xyz;
// vec3 d1 = gl_in[1].gl_Position.xyz;
// vec3 d2 = gl_in[2].gl_Position.xyz;
// vec3 n_u = d1 - d0;
// vec3 v_u = d2 - d0;
// vec3 v_normal = normalize(cross(n_u, v_u));
// vec3 normal = cross(tangentZ, tangentX);
// gl_Position = c;
// outData.tex_coord = base_uv;
// // outData.pw = vec3(c);
// // outData.nw = normal;
// // Interpolate the position using the barycentric coordinates from tessellation
// // vec3 pos = mix(mix(gl_in[0].gl_Position.xyz, gl_in[1].gl_Position.xyz, gl_TessCoord.x),
// // mix(gl_in[3].gl_Position.xyz, gl_in[2].gl_Position.xyz, gl_TessCoord.x),
// // gl_TessCoord.y);
// // frag_position = pos;
// // outData.tex_coord = mix(mix(inData[0].tex_coord, inData[1].tex_coord, gl_TessCoord.x),
// // mix(inData[3].tex_coord, inData[2].tex_coord, gl_TessCoord.x),
// // gl_TessCoord.y);
// // gl_Position = PV*M*vec4(pos, 1.0);
// }