Files
projecte_2026/source/core/rendering/pixel_reveal.cpp

108 lines
4.1 KiB
C++

#include "core/rendering/pixel_reveal.hpp"
#include <algorithm> // Para min, ranges::all_of
#include <numeric> // Para iota
#include <queue> // Para queue (BFS en modo ORDERED)
#include <random> // Para mt19937, shuffle
#include "core/rendering/surface.hpp" // Para Surface
#include "utils/utils.hpp" // Para PaletteColor
// Constructor
PixelReveal::PixelReveal(int width, int height, float pixels_per_second, float step_duration, int num_steps, bool reverse, RevealMode mode)
: cover_surface_(std::make_shared<Surface>(width, height)),
reveal_order_(height),
row_step_(height, 0),
width_(width),
height_(height),
pixels_per_second_(pixels_per_second),
step_duration_(step_duration),
num_steps_(num_steps),
reverse_(reverse),
mode_(mode) {
// En modo normal: empieza negro sólido (se irá revelando a transparente)
// En modo inverso: empieza transparente (se irá cubriendo de negro)
const auto INITIAL_COLOR = reverse_ ? 255 : 0;
cover_surface_->clear(INITIAL_COLOR);
if (mode_ == RevealMode::ORDERED) {
// Calcula offsets por bisección BFS: 0, N/2, N/4, 3N/4, ...
std::vector<int> offsets;
offsets.push_back(0);
std::queue<std::pair<int, int>> bq;
bq.emplace(0, num_steps_);
while (static_cast<int>(offsets.size()) < num_steps_) {
auto [lo, hi] = bq.front();
bq.pop();
if (hi - lo <= 1) {
continue;
}
const int MID = (lo + hi) / 2;
offsets.push_back(MID);
bq.emplace(lo, MID);
bq.emplace(MID, hi);
}
// Genera el orden: para cada offset, todas las columnas col = offset, offset+N, offset+2N, ...
std::vector<int> ordered_cols;
ordered_cols.reserve(width_);
for (const int OFF : offsets) {
for (int col = OFF; col < width_; col += num_steps_) {
ordered_cols.push_back(col);
}
}
// Todas las filas usan el mismo orden (sin aleatoriedad)
for (int r = 0; r < height_; r++) {
reveal_order_[r] = ordered_cols;
}
} else {
// Modo RANDOM: orden aleatorio por fila usando la fila como semilla (reproducible)
for (int r = 0; r < height_; r++) {
reveal_order_[r].resize(width_);
std::iota(reveal_order_[r].begin(), reveal_order_[r].end(), 0);
std::mt19937 rng(static_cast<unsigned int>(r));
std::shuffle(reveal_order_[r].begin(), reveal_order_[r].end(), rng);
}
}
}
// Actualiza el estado del revelado
void PixelReveal::update(float time_active) { // NOLINT(readability-make-member-function-const)
// En modo normal revela (pone transparente); en modo inverso cubre (pone negro)
const auto PIXEL_COLOR = reverse_ ? 0 : 255;
for (int r = 0; r < height_; r++) {
const float T_START = static_cast<float>(r) / pixels_per_second_;
const float TIME_IN_ROW = time_active - T_START;
if (TIME_IN_ROW < 0.0F) {
continue; // Esta fila aún no ha empezado
}
const int STEPS = std::min(num_steps_, static_cast<int>(TIME_IN_ROW / step_duration_));
if (STEPS > row_step_[r]) {
// Procesa los píxeles de los pasos pendientes
for (int step = row_step_[r]; step < STEPS; step++) {
const int START_IDX = step * width_ / num_steps_;
const int END_IDX = (step == num_steps_ - 1) ? width_ : (step + 1) * width_ / num_steps_;
for (int idx = START_IDX; idx < END_IDX; idx++) {
const int COL = reveal_order_[r][idx];
cover_surface_->putPixel(COL, r, PIXEL_COLOR);
}
}
row_step_[r] = STEPS;
}
}
}
// Dibuja la máscara en la posición indicada
void PixelReveal::render(int dst_x, int dst_y) const {
cover_surface_->render(dst_x, dst_y);
}
// Indica si el revelado ha completado todas las filas
auto PixelReveal::isComplete() const -> bool {
return std::ranges::all_of(row_step_, [this](int s) -> bool { return s >= num_steps_; });
}