ImageGeneric(const std::vector<unsigned int>& stride, const std::vector<unsigned int>& rows, std::mt19937& rng) {
// count planes
assert(stride.size() == rows.size());
unsigned int planes = stride.size();
m_data.resize(planes);
m_stride.resize(planes);
// calculate stride and total size
size_t totalsize = 0;
for(unsigned int p = 0; p < planes; ++p) {
m_stride[p] = grow_align16(stride[p]);
totalsize += m_stride[p] * rows[p];
}
// allocate buffer
m_buffer.Alloc(totalsize);
for(unsigned int i = 0; i < totalsize; ++i) {
m_buffer[i] = rng();
}
// set data
uint8_t *data = m_buffer.GetData();
for(unsigned int p = 0; p < planes; ++p) {
m_data[p] = data;
data += m_stride[p] * rows[p];
}
}
void Scale_BGRA_Generic(unsigned int in_w, unsigned int in_h, const uint8_t* in_data, int in_stride,
unsigned int out_w, unsigned int out_h, uint8_t* out_data, int out_stride,
MipMapFunction mipmap_function, BilinearFunction bilinear_function) {
// no scaling?
if(in_w == out_w && in_h == out_h) {
if(in_stride == out_stride) {
memcpy(out_data, in_data, in_stride * in_h);
} else {
for(unsigned int out_j = 0; out_j < out_h; ++out_j) {
memcpy(out_data, in_data, in_w * 4);
in_data += in_stride;
out_data += out_stride;
}
}
return;
}
// calculate mipmap factors
unsigned int mx = 0, my = 0;
while((out_w << (mx + 1)) <= in_w) ++mx;
while((out_h << (my + 1)) <= in_h) ++my;
if(mx + my > 8) {
if(mx <= 4)
my = 8 - mx;
else if(my <= 4)
mx = 8 - my;
else
mx = my = 4;
}
// pure mipmap scaling?
if((out_w << mx) == in_w && (out_h << my) == in_h) {
mipmap_function(in_w, in_h, in_data, in_stride, out_data, out_stride, mx, my);
return;
}
// create mipmap
TempBuffer<uint8_t> mipmap;
if(mx != 0 || my != 0) {
unsigned int mipmap_w = ((in_w - 1) >> mx) + 1, mipmap_h = ((in_h - 1) >> my) + 1;
int mipmap_stride = grow_align16(mipmap_w * 4);
mipmap.Alloc(mipmap_stride * mipmap_h);
mipmap_function(in_w, in_h, in_data, in_stride, mipmap.GetData(), mipmap_stride, mx, my);
in_data = mipmap.GetData();
in_stride = mipmap_stride;
}