public TransientBuffer Alloc(uint size)
{
var tb = new TransientBuffer
{
size = size
};
for (int i = 0; i < buffers.Count; i++)
{
ref TransientBufferDesc tbc = ref buffers.At(i);
if (tbc.size + size < tbc.buffer.Size)
{
tb.offset = tbc.size;
tb.buffer = tbc.buffer;
tbc.size += MathUtil.Align(size, (uint)alignment);
return(tb);
}
}
/*
* public static void CalculateMeshTangents(FastList<VertexPosTexNorm> vertices,
* FastList<VertexPosTexNTB> tangentVertices, List<uint[]> trianglesList)
* {
* //speed up math by copying the mesh arrays
* //variable definitions
* int vertexCount = vertices.Count;
*
* vec3[] tan1 = new vec3[vertexCount];
* vec3[] tan2 = new vec3[vertexCount];
*
* vec4[] tangents = new vec4[vertexCount];
*
* foreach (var triangles in trianglesList)
* {
* int triangleCount = triangles.Length;
* for (long a = 0; a < triangleCount; a += 3)
* {
* int i1 = (int)triangles[a + 0];
* int i2 = (int)triangles[a + 1];
* int i3 = (int)triangles[a + 2];
*
* vec3 v1 = vertices[i1].position;
* vec3 v2 = vertices[i2].position;
* vec3 v3 = vertices[i3].position;
*
* vec2 w1 = vertices[i1].texcoord;
* vec2 w2 = vertices[i2].texcoord;
* vec2 w3 = vertices[i3].texcoord;
*
* float x1 = v2.x - v1.x;
* float x2 = v3.x - v1.x;
* float y1 = v2.y - v1.y;
* float y2 = v3.y - v1.y;
* float z1 = v2.z - v1.z;
* float z2 = v3.z - v1.z;
*
* float s1 = w2.x - w1.x;
* float s2 = w3.x - w1.x;
* float t1 = w2.y - w1.y;
* float t2 = w3.y - w1.y;
*
* float r = 1.0f / (s1 * t2 - s2 * t1);
*
* vec3 sdir = new vec3((t2 * x1 - t1 * x2) * r, (t2 * y1 - t1 * y2) * r, (t2 * z1 - t1 * z2) * r);
* vec3 tdir = new vec3((s1 * x2 - s2 * x1) * r, (s1 * y2 - s2 * y1) * r, (s1 * z2 - s2 * z1) * r);
*
* tan1[i1] += sdir;
* tan1[i2] += sdir;
* tan1[i3] += sdir;
*
* tan2[i1] += tdir;
* tan2[i2] += tdir;
* tan2[i3] += tdir;
* }
* }
*
* for (int a = 0; a < vertexCount; ++a)
* {
* vec3 n = vertices[a].normal;
* vec3 t = tan1[a];
* if (t == vec3.Zero)
* {
* continue;
* }
*
* ref var newVertex = ref tangentVertices.At(a);
* newVertex.position = vertices[a].position;
* newVertex.texcoord = vertices[a].texcoord;
* newVertex.normal = vertices[a].normal;
*
* vec3 tmp = glm.normalize(t - n * vec3.Dot(n, t));
*
* var tangent = new vec4(tmp.x, tmp.y, tmp.z, 0);
* tangent.w = (vec3.Dot(vec3.Cross(t, n), tan2[a]) < 0.0f) ? -1.0f : 1.0f;
* newVertex.tangent = tangent;
* }
*
* }*/
void CreateTangentSpaceTangents(FastList <VertexPosTexNorm> vertices,
FastList <VertexPosTexNTB> tangentVertices, List <uint[]> trianglesList)
{
vec3 v0, v1, v2;
vec3 p0, p1, p2;
vec3 d1, d2;
float[,] uv = new float[3, 2];
float det, u, v, l1, l2;
int vertexCount = vertices.Count;
vec3[] sVector = new vec3[vertexCount];
vec3[] tVector = new vec3[vertexCount];
foreach (var indices in trianglesList)
{
int faceCount = indices.Length;
for (int k = 0; k < faceCount; k += 3)
{
v0 = vertices[(int)indices[k]].position;
v1 = vertices[(int)indices[k + 1]].position - v0;
v2 = vertices[(int)indices[k + 2]].position - v0;
uv[0, 0] = vertices[(int)indices[k]].texcoord.x;
uv[0, 1] = vertices[(int)indices[k]].texcoord.y;
uv[1, 0] = vertices[(int)indices[k + 1]].texcoord.x - uv[0, 0];
uv[1, 1] = vertices[(int)indices[k + 1]].texcoord.y - uv[0, 1];
uv[2, 0] = vertices[(int)indices[k + 2]].texcoord.x - uv[0, 0];
uv[2, 1] = vertices[(int)indices[k + 2]].texcoord.y - uv[0, 1];
det = (uv[1, 0] * uv[2, 1]) - (uv[2, 0] * uv[1, 1]);
if (Math.Abs(det) < 0.000001f)
{
continue;
}
u = 0; v = 0;
u -= uv[0, 0];
v -= uv[0, 1];
p0 = v0 + v1 * ((u * uv[2, 1] - uv[2, 0] * v) / det) + v2 * ((uv[1, 0] * v - u * uv[1, 1]) / det);
u = 1; v = 0;
u -= uv[0, 0];
v -= uv[0, 1];
p1 = v0 + v1 * ((u * uv[2, 1] - uv[2, 0] * v) / det) + v2 * ((uv[1, 0] * v - u * uv[1, 1]) / det);
u = 0; v = 1;
u -= uv[0, 0]; v -= uv[0, 1];
p2 = v0 + v1 * ((u * uv[2, 1] - uv[2, 0] * v) / det) + v2 * ((uv[1, 0] * v - u * uv[1, 1]) / det);
d1 = p2 - p0;
d2 = p1 - p0;
l1 = glm.length(d1);
l2 = glm.length(d2);
d1 *= 1.0f / l1;
d2 *= 1.0f / l2;
int j = (int)indices[k];
sVector[j] += d1;
tVector[j].x += d2.x; tVector[j].y += d2.y; tVector[j].z += d2.z;
j = (int)indices[k + 1];
sVector[j].x += d1.x; sVector[j].y += d1.y; sVector[j].z += d1.z;
tVector[j].x += d2.x; tVector[j].y += d2.y; tVector[j].z += d2.z;
j = (int)indices[k + 2];
sVector[j].x += d1.x; sVector[j].y += d1.y; sVector[j].z += d1.z;
tVector[j].x += d2.x; tVector[j].y += d2.y; tVector[j].z += d2.z;
}
}
for (int i = 0; i < vertexCount; i++)
{
v0 = sVector[i];
v0 = NormalizeRobust(v0);
v1 = tVector[i];
vec3 n = glm.vec3(vertices[i].normal.x, vertices[i].normal.y, vertices[i].normal.z);
if (glm.length2(v1) < 0.0001f)
{
v1 = glm.cross(v0, n);
}
v1 = NormalizeRobust(v1);
sVector[i] = v0;
tVector[i].x = v1.x;
tVector[i].y = v1.y;
tVector[i].z = v1.z;
ref var newVertex = ref tangentVertices.At(i);
newVertex.position = vertices[i].position;
newVertex.texcoord = vertices[i].texcoord;
newVertex.normal = n;
newVertex.tangent = tVector[i];
newVertex.bitangent = sVector[i];
}