virtualx-engine/servers/rendering/renderer_rd/shaders/skeleton.glsl
clayjohn 51ed3aef63 Vertex and attribute compression to reduce the size of the vertex format.
This allows Godot to automatically compress meshes to save a lot of bandwidth.

In general, this requires no interaction from the user and should result in
no noticable quality loss.

This scheme is not backwards compatible, so we have provided an upgrade
mechanism, and a mesh versioning mechanism.

Existing meshes can still be used as a result, but users can get a
performance boost by reimporting assets.
2023-10-05 12:02:23 -06:00

306 lines
10 KiB
GLSL

#[compute]
#version 450
#VERSION_DEFINES
layout(local_size_x = 64, local_size_y = 1, local_size_z = 1) in;
layout(set = 0, binding = 1, std430) buffer restrict writeonly DstVertexData {
uint data[];
}
dst_vertices;
layout(set = 0, binding = 2, std430) buffer restrict readonly BlendShapeWeights {
float data[];
}
blend_shape_weights;
layout(set = 1, binding = 0, std430) buffer restrict readonly SrcVertexData {
uint data[];
}
src_vertices;
layout(set = 1, binding = 1, std430) buffer restrict readonly BoneWeightData {
uint data[];
}
src_bone_weights;
layout(set = 1, binding = 2, std430) buffer restrict readonly BlendShapeData {
uint data[];
}
src_blend_shapes;
layout(set = 2, binding = 0, std430) buffer restrict readonly SkeletonData {
vec4 data[];
}
bone_transforms;
layout(push_constant, std430) uniform Params {
bool has_normal;
bool has_tangent;
bool has_skeleton;
bool has_blend_shape;
uint vertex_count;
uint vertex_stride;
uint skin_stride;
uint skin_weight_offset;
uint blend_shape_count;
bool normalized_blend_shapes;
uint normal_tangent_stride;
uint pad1;
vec2 skeleton_transform_x;
vec2 skeleton_transform_y;
vec2 skeleton_transform_offset;
vec2 inverse_transform_x;
vec2 inverse_transform_y;
vec2 inverse_transform_offset;
}
params;
vec2 uint_to_vec2(uint base) {
uvec2 decode = (uvec2(base) >> uvec2(0, 16)) & uvec2(0xFFFF, 0xFFFF);
return vec2(decode) / vec2(65535.0, 65535.0) * 2.0 - 1.0;
}
vec3 oct_to_vec3(vec2 oct) {
vec3 v = vec3(oct.xy, 1.0 - abs(oct.x) - abs(oct.y));
float t = max(-v.z, 0.0);
v.xy += t * -sign(v.xy);
return normalize(v);
}
vec3 decode_uint_oct_to_norm(uint base) {
return oct_to_vec3(uint_to_vec2(base));
}
vec4 decode_uint_oct_to_tang(uint base) {
vec2 oct_sign_encoded = uint_to_vec2(base);
// Binormal sign encoded in y component
vec2 oct = vec2(oct_sign_encoded.x, abs(oct_sign_encoded.y) * 2.0 - 1.0);
return vec4(oct_to_vec3(oct), sign(oct_sign_encoded.y));
}
vec2 signNotZero(vec2 v) {
return mix(vec2(-1.0), vec2(1.0), greaterThanEqual(v.xy, vec2(0.0)));
}
uint vec2_to_uint(vec2 base) {
uvec2 enc = uvec2(clamp(ivec2(base * vec2(65535, 65535)), ivec2(0), ivec2(0xFFFF, 0xFFFF))) << uvec2(0, 16);
return enc.x | enc.y;
}
vec2 vec3_to_oct(vec3 e) {
e /= abs(e.x) + abs(e.y) + abs(e.z);
vec2 oct = e.z >= 0.0f ? e.xy : (vec2(1.0f) - abs(e.yx)) * signNotZero(e.xy);
return oct * 0.5f + 0.5f;
}
uint encode_norm_to_uint_oct(vec3 base) {
return vec2_to_uint(vec3_to_oct(base));
}
uint encode_tang_to_uint_oct(vec4 base) {
vec2 oct = vec3_to_oct(base.xyz);
// Encode binormal sign in y component
oct.y = oct.y * 0.5f + 0.5f;
oct.y = base.w >= 0.0f ? oct.y : 1 - oct.y;
return vec2_to_uint(oct);
}
void main() {
uint index = gl_GlobalInvocationID.x;
if (index >= params.vertex_count) {
return;
}
uint src_offset = index * params.vertex_stride;
#ifdef MODE_2D
vec2 vertex = uintBitsToFloat(uvec2(src_vertices.data[src_offset + 0], src_vertices.data[src_offset + 1]));
if (params.has_blend_shape) {
float blend_total = 0.0;
vec2 blend_vertex = vec2(0.0);
for (uint i = 0; i < params.blend_shape_count; i++) {
float w = blend_shape_weights.data[i];
if (abs(w) > 0.0001) {
uint base_offset = (params.vertex_count * i + index) * params.vertex_stride;
blend_vertex += uintBitsToFloat(uvec2(src_blend_shapes.data[base_offset + 0], src_blend_shapes.data[base_offset + 1])) * w;
base_offset += 2;
blend_total += w;
}
}
if (params.normalized_blend_shapes) {
vertex = (1.0 - blend_total) * vertex;
}
vertex += blend_vertex;
}
if (params.has_skeleton) {
uint skin_offset = params.skin_stride * index;
uvec2 bones = uvec2(src_bone_weights.data[skin_offset + 0], src_bone_weights.data[skin_offset + 1]);
uvec2 bones_01 = uvec2(bones.x & 0xFFFF, bones.x >> 16) * 2; //pre-add xform offset
uvec2 bones_23 = uvec2(bones.y & 0xFFFF, bones.y >> 16) * 2;
skin_offset += params.skin_weight_offset;
uvec2 weights = uvec2(src_bone_weights.data[skin_offset + 0], src_bone_weights.data[skin_offset + 1]);
vec2 weights_01 = unpackUnorm2x16(weights.x);
vec2 weights_23 = unpackUnorm2x16(weights.y);
mat4 m = mat4(bone_transforms.data[bones_01.x], bone_transforms.data[bones_01.x + 1], vec4(0.0, 0.0, 1.0, 0.0), vec4(0.0, 0.0, 0.0, 1.0)) * weights_01.x;
m += mat4(bone_transforms.data[bones_01.y], bone_transforms.data[bones_01.y + 1], vec4(0.0, 0.0, 1.0, 0.0), vec4(0.0, 0.0, 0.0, 1.0)) * weights_01.y;
m += mat4(bone_transforms.data[bones_23.x], bone_transforms.data[bones_23.x + 1], vec4(0.0, 0.0, 1.0, 0.0), vec4(0.0, 0.0, 0.0, 1.0)) * weights_23.x;
m += mat4(bone_transforms.data[bones_23.y], bone_transforms.data[bones_23.y + 1], vec4(0.0, 0.0, 1.0, 0.0), vec4(0.0, 0.0, 0.0, 1.0)) * weights_23.y;
mat4 skeleton_matrix = mat4(vec4(params.skeleton_transform_x, 0.0, 0.0), vec4(params.skeleton_transform_y, 0.0, 0.0), vec4(0.0, 0.0, 1.0, 0.0), vec4(params.skeleton_transform_offset, 0.0, 1.0));
mat4 inverse_matrix = mat4(vec4(params.inverse_transform_x, 0.0, 0.0), vec4(params.inverse_transform_y, 0.0, 0.0), vec4(0.0, 0.0, 1.0, 0.0), vec4(params.inverse_transform_offset, 0.0, 1.0));
m = skeleton_matrix * transpose(m) * inverse_matrix;
vertex = (m * vec4(vertex, 0.0, 1.0)).xy;
}
uint dst_offset = index * params.vertex_stride;
uvec2 uvertex = floatBitsToUint(vertex);
dst_vertices.data[dst_offset + 0] = uvertex.x;
dst_vertices.data[dst_offset + 1] = uvertex.y;
#else
vec3 vertex;
vec3 normal;
vec4 tangent;
vertex = uintBitsToFloat(uvec3(src_vertices.data[src_offset + 0], src_vertices.data[src_offset + 1], src_vertices.data[src_offset + 2]));
uint src_normal = params.vertex_count * params.vertex_stride + index * params.normal_tangent_stride;
if (params.has_normal) {
normal = decode_uint_oct_to_norm(src_vertices.data[src_normal]);
src_normal++;
}
if (params.has_tangent) {
tangent = decode_uint_oct_to_tang(src_vertices.data[src_normal]);
}
if (params.has_blend_shape) {
float blend_total = 0.0;
vec3 blend_vertex = vec3(0.0);
vec3 blend_normal = vec3(0.0);
vec3 blend_tangent = vec3(0.0);
for (uint i = 0; i < params.blend_shape_count; i++) {
float w = blend_shape_weights.data[i];
if (abs(w) > 0.0001) {
uint base_offset = params.vertex_count * i * (params.vertex_stride + params.normal_tangent_stride) + index * params.vertex_stride;
blend_vertex += uintBitsToFloat(uvec3(src_blend_shapes.data[base_offset + 0], src_blend_shapes.data[base_offset + 1], src_blend_shapes.data[base_offset + 2])) * w;
uint base_normal = params.vertex_count * i * (params.vertex_stride + params.normal_tangent_stride) + params.vertex_count * params.vertex_stride + index * params.normal_tangent_stride;
if (params.has_normal) {
blend_normal += decode_uint_oct_to_norm(src_blend_shapes.data[base_normal]) * w;
base_normal++;
}
if (params.has_tangent) {
blend_tangent += decode_uint_oct_to_tang(src_blend_shapes.data[base_normal]).rgb * w;
}
blend_total += w;
}
}
if (params.normalized_blend_shapes) {
vertex = (1.0 - blend_total) * vertex;
normal = (1.0 - blend_total) * normal;
tangent.rgb = (1.0 - blend_total) * tangent.rgb;
}
vertex += blend_vertex;
normal = normalize(normal + blend_normal);
tangent.rgb = normalize(tangent.rgb + blend_tangent);
}
if (params.has_skeleton) {
uint skin_offset = params.skin_stride * index;
uvec2 bones = uvec2(src_bone_weights.data[skin_offset + 0], src_bone_weights.data[skin_offset + 1]);
uvec2 bones_01 = uvec2(bones.x & 0xFFFF, bones.x >> 16) * 3; //pre-add xform offset
uvec2 bones_23 = uvec2(bones.y & 0xFFFF, bones.y >> 16) * 3;
skin_offset += params.skin_weight_offset;
uvec2 weights = uvec2(src_bone_weights.data[skin_offset + 0], src_bone_weights.data[skin_offset + 1]);
vec2 weights_01 = unpackUnorm2x16(weights.x);
vec2 weights_23 = unpackUnorm2x16(weights.y);
mat4 m = mat4(bone_transforms.data[bones_01.x], bone_transforms.data[bones_01.x + 1], bone_transforms.data[bones_01.x + 2], vec4(0.0, 0.0, 0.0, 1.0)) * weights_01.x;
m += mat4(bone_transforms.data[bones_01.y], bone_transforms.data[bones_01.y + 1], bone_transforms.data[bones_01.y + 2], vec4(0.0, 0.0, 0.0, 1.0)) * weights_01.y;
m += mat4(bone_transforms.data[bones_23.x], bone_transforms.data[bones_23.x + 1], bone_transforms.data[bones_23.x + 2], vec4(0.0, 0.0, 0.0, 1.0)) * weights_23.x;
m += mat4(bone_transforms.data[bones_23.y], bone_transforms.data[bones_23.y + 1], bone_transforms.data[bones_23.y + 2], vec4(0.0, 0.0, 0.0, 1.0)) * weights_23.y;
if (params.skin_weight_offset == 4) {
//using 8 bones/weights
skin_offset = params.skin_stride * index + 2;
bones = uvec2(src_bone_weights.data[skin_offset + 0], src_bone_weights.data[skin_offset + 1]);
bones_01 = uvec2(bones.x & 0xFFFF, bones.x >> 16) * 3; //pre-add xform offset
bones_23 = uvec2(bones.y & 0xFFFF, bones.y >> 16) * 3;
skin_offset += params.skin_weight_offset;
weights = uvec2(src_bone_weights.data[skin_offset + 0], src_bone_weights.data[skin_offset + 1]);
weights_01 = unpackUnorm2x16(weights.x);
weights_23 = unpackUnorm2x16(weights.y);
m += mat4(bone_transforms.data[bones_01.x], bone_transforms.data[bones_01.x + 1], bone_transforms.data[bones_01.x + 2], vec4(0.0, 0.0, 0.0, 1.0)) * weights_01.x;
m += mat4(bone_transforms.data[bones_01.y], bone_transforms.data[bones_01.y + 1], bone_transforms.data[bones_01.y + 2], vec4(0.0, 0.0, 0.0, 1.0)) * weights_01.y;
m += mat4(bone_transforms.data[bones_23.x], bone_transforms.data[bones_23.x + 1], bone_transforms.data[bones_23.x + 2], vec4(0.0, 0.0, 0.0, 1.0)) * weights_23.x;
m += mat4(bone_transforms.data[bones_23.y], bone_transforms.data[bones_23.y + 1], bone_transforms.data[bones_23.y + 2], vec4(0.0, 0.0, 0.0, 1.0)) * weights_23.y;
}
//reverse order because its transposed
vertex = (vec4(vertex, 1.0) * m).xyz;
normal = normalize((vec4(normal, 0.0) * m).xyz);
tangent.xyz = normalize((vec4(tangent.xyz, 0.0) * m).xyz);
}
uint dst_offset = index * params.vertex_stride;
uvec3 uvertex = floatBitsToUint(vertex);
dst_vertices.data[dst_offset + 0] = uvertex.x;
dst_vertices.data[dst_offset + 1] = uvertex.y;
dst_vertices.data[dst_offset + 2] = uvertex.z;
uint dst_normal = params.vertex_count * params.vertex_stride + index * params.normal_tangent_stride;
if (params.has_normal) {
dst_vertices.data[dst_normal] = encode_norm_to_uint_oct(normal);
dst_normal++;
}
if (params.has_tangent) {
dst_vertices.data[dst_normal] = encode_tang_to_uint_oct(tangent);
}
#endif
}