Files
ppsspp/Common/Render/AtlasGen.cpp
T
2025-09-22 15:24:10 -06:00

300 lines
8.2 KiB
C++

#include <assert.h>
#include <png.h>
#include <set>
#include <map>
#include <vector>
#include <algorithm>
#include <string>
#include <cmath>
#include "Common/StringUtils.h"
#include "Common/Render/TextureAtlas.h"
#include "Common/Data/Format/PNGLoad.h"
#include "Common/Data/Format/ZIMSave.h"
#include "Common/Data/Encoding/Utf8.h"
#include "Common/File/VFS/VFS.h"
#include "Common/Render/AtlasGen.h"
typedef unsigned short u16;
void Image::copyfrom(const Image &img, int ox, int oy, bool redToWhiteAlpha) {
assert(img.width() + ox <= width());
assert(img.height() + oy <= height());
for (int y = 0; y < (int)img.height(); y++) {
for (int x = 0; x < (int)img.width(); x++) {
if (!redToWhiteAlpha) {
set1(x + ox, y + oy, img.get1(x, y));
} else {
set1(x + ox, y + oy, 0x00FFFFFF | (img.get1(x, y) << 24));
}
}
}
}
bool Image::LoadPNG(const char *png_name) {
size_t sz;
const uint8_t *file_data = g_VFS.ReadFile(png_name, &sz);
if (!file_data) {
printf("Failed to load png from VFS");
return false;
}
unsigned char *img_data;
int w, h;
if (1 != pngLoadPtr(file_data, sz, &w, &h, &img_data)) {
delete[] file_data;
printf("Failed to load %s\n", png_name);
return false;
}
delete[] file_data;
resize(w, h);
memcpy(dat.data(), img_data, 4 * w * h);
free(img_data);
return true;
}
void Image::SavePNG(const char *png_name) {
pngSave(Path(png_name), dat.data(), w, h, 4);
}
void Image::SaveZIM(const char *zim_name, int zim_format) {
uint8_t *image_data = new uint8_t[width() * height() * 4];
for (int y = 0; y < height(); y++) {
memcpy(image_data + y * width() * 4, (dat.data() + y * w), width() * 4);
}
FILE *f = fopen(zim_name, "wb");
// SaveZIM takes ownership over image_data, there's no leak.
::SaveZIM(f, width(), height(), width() * 4, zim_format | ZIM_DITHER, image_data);
fclose(f);
}
void Bucket::AddImage(Image &&img, int id) {
Data dat{};
dat.id = id;
dat.sx = 0;
dat.sy = 0;
dat.ex = (int)img.width();
dat.ey = (int)img.height();
dat.w = dat.ex;
dat.h = dat.ey;
dat.scale = img.scale;
dat.redToWhiteAlpha = false;
images.emplace_back(std::move(img));
data.push_back(dat);
}
inline bool CompareByID(const Data &lhs, const Data &rhs) {
return lhs.id < rhs.id; // should be unique
}
inline bool CompareByArea(const Data& lhs, const Data& rhs) {
return lhs.w * lhs.h > rhs.w * rhs.h;
}
std::vector<Data> Bucket::Resolve(int image_width, Image &dest) {
// Place all the little images - whatever they are.
// Uses greedy fill algorithm. Slow but works surprisingly well, CPUs are fast.
ImageU8 masq;
masq.resize(image_width, 1);
dest.resize(image_width, 1);
std::sort(data.begin(), data.end(), CompareByArea);
for (int i = 0; i < (int)data.size(); i++) {
if ((i + 1) % 2000 == 0) {
printf("Resolving (%i / %i)\n", i, (int)data.size());
}
int idx = (int)data[i].w;
int idy = (int)data[i].h;
if (idx > 1 && idy > 1) {
assert(idx <= image_width);
for (int ty = 0; ty < 2047; ty++) {
if (ty + idy + 1 > (int)dest.height()) {
// Every 16 lines of new space needed, grow the image.
masq.resize(image_width, ty + idy + 16);
dest.resize(image_width, ty + idy + 16);
}
// Brute force packing.
int sz = (int)data[i].w;
auto &masq_ty = masq.dat[ty];
auto &masq_idy = masq.dat[ty + idy - 1];
for (int tx = 0; tx < image_width - sz; tx++) {
bool valid = !(masq_ty[tx] || masq_idy[tx] || masq_ty[tx + idx - 1] || masq_idy[tx + idx - 1]);
if (valid) {
for (int ity = 0; ity < idy && valid; ity++) {
for (int itx = 0; itx < idx && valid; itx++) {
if (masq.dat[ty + ity][tx + itx]) {
goto skip;
}
}
}
masq.set(tx, ty, tx + idx + 1, ty + idy + 1, 255);
data[i].sx = tx;
data[i].sy = ty;
data[i].ex = tx + idx;
data[i].ey = ty + idy;
// printf("Placed %d at %dx%d-%dx%d\n", items[i].second.id, tx, ty, tx + idx, ty + idy);
goto found;
}
skip:
;
}
}
found:
;
}
}
// Sort the data back by ID.
std::sort(data.begin(), data.end(), CompareByID);
// Actually copy the image data in place, after doing the layout.
for (int i = 0; i < (int)data.size(); i++) {
dest.copyfrom(images[i], data[i].sx, data[i].sy, data[i].redToWhiteAlpha);
}
return data;
}
AtlasImage ToAtlasImage(int id, std::string_view name, float tw, float th, const std::vector<Data> &results) {
AtlasImage img{};
const int i = id;
const float toffx = 0.5f / tw;
const float toffy = 0.5f / th;
img.u1 = results[i].sx / tw + toffx;
img.v1 = results[i].sy / th + toffy;
img.u2 = results[i].ex / tw - toffx;
img.v2 = results[i].ey / th - toffy;
// The w and h here is the UI-pixels width/height. So if we rasterized at another DPI than 1.0f, we need to scale here.
img.w = results[i].w / results[i].scale;
img.h = results[i].h / results[i].scale;
truncate_cpy(img.name, name);
return img;
}
// The below is ChatGPT-generated drop shadow code. Needs optimization!
static std::vector<float> makeGaussianKernel(int radius) {
const float sigma = radius / 2.0f;
std::vector<float> kernel(2 * radius + 1);
float sum = 0.0f;
for (int i = -radius; i <= radius; i++) {
float val = std::exp(-(i * i) / (2 * sigma * sigma));
kernel[i + radius] = val;
sum += val;
}
for (float &v : kernel) v /= sum;
return kernel;
}
static void blurAlpha(const std::vector<float> &src, std::vector<float> &dst, int w, int h, int radius) {
auto kernel = makeGaussianKernel(radius);
int ksize = (int)kernel.size();
int kr = radius;
std::vector<float> tmp(w * h, 0.0f);
// horizontal
for (int y = 0; y < h; y++) {
for (int x = 0; x < w; x++) {
float sum = 0.0f;
for (int k = -kr; k <= kr; k++) {
int xx = std::clamp(x + k, 0, w - 1);
sum += src[y * w + xx] * kernel[k + kr];
}
tmp[y * w + x] = sum;
}
}
// vertical
for (int y = 0; y < h; y++) {
for (int x = 0; x < w; x++) {
float sum = 0.0f;
for (int k = -kr; k <= kr; k++) {
int yy = std::clamp(y + k, 0, h - 1);
sum += tmp[yy * w + x] * kernel[k + kr];
}
dst[y * w + x] = sum;
}
}
}
inline u32 blendOver(u32 dst, u32 src) {
// Extract channels
float sa = ((src >> 24) & 0xFF) / 255.0f;
float sr = ((src >> 16) & 0xFF) / 255.0f;
float sg = ((src >> 8) & 0xFF) / 255.0f;
float sb = ((src >> 0) & 0xFF) / 255.0f;
float da = ((dst >> 24) & 0xFF) / 255.0f;
float dr = ((dst >> 16) & 0xFF) / 255.0f;
float dg = ((dst >> 8) & 0xFF) / 255.0f;
float db = ((dst >> 0) & 0xFF) / 255.0f;
// Source over
float outA = sa + da * (1.0f - sa);
float outR = (sr * sa + dr * da * (1.0f - sa)) / (outA > 0 ? outA : 1);
float outG = (sg * sa + dg * da * (1.0f - sa)) / (outA > 0 ? outA : 1);
float outB = (sb * sa + db * da * (1.0f - sa)) / (outA > 0 ? outA : 1);
return ((u32)(outA * 255 + 0.5f) << 24) |
((u32)(outR * 255 + 0.5f) << 16) |
((u32)(outG * 255 + 0.5f) << 8) |
((u32)(outB * 255 + 0.5f) << 0);
}
void AddDropShadow(Image &img, int shadowSize, float intensity) {
int radius = std::max(1, (int)(shadowSize * img.scale));
// Expand canvas so blur has space on all sides
int newW = img.w + radius * 2;
int newH = img.h + radius * 2;
// Expanded alpha buffer
std::vector<float> alpha(newW * newH, 0.0f);
for (int y = 0; y < img.h; y++) {
for (int x = 0; x < img.w; x++) {
float a = ((img.dat[y * img.w + x] >> 24) & 0xFF) / 255.0f;
alpha[(y + radius) * newW + (x + radius)] = a;
}
}
// Blur the expanded alpha
std::vector<float> blurred(newW * newH, 0.0f);
blurAlpha(alpha, blurred, newW, newH, radius);
// Target buffer with transparent background
std::vector<u32> newData(newW * newH, 0);
// Draw shadow (black, blurred alpha)
for (int y = 0; y < newH; y++) {
for (int x = 0; x < newW; x++) {
float a = blurred[y * newW + x];
if (a > 0.001f) {
u32 shadowColor = ((u32)(a * 255 * intensity) << 24); // semi-transparent black
newData[y * newW + x] = blendOver(newData[y * newW + x], shadowColor);
}
}
}
// Composite original image on top (centered in expanded buffer)
for (int y = 0; y < img.h; y++) {
for (int x = 0; x < img.w; x++) {
u32 c = img.dat[y * img.w + x];
if ((c >> 24) & 0xFF) {
int nx = x + radius;
int ny = y + radius;
newData[ny * newW + nx] = blendOver(newData[ny * newW + nx], c);
}
}
}
img.w = newW;
img.h = newH;
img.dat = std::move(newData);
}