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// Copyright (C) 2025 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
#include "imagetestingrenderer.h"
#include "imagetestingitem.h"
#include <QColor>
#include <QRandomGenerator>
#include <QTimer>
#include "qcanvaslineargradient.h"
ImageTestingRenderer::ImageTestingRenderer()
{
}
void ImageTestingRenderer::synchronizeData(QCanvasPainterItem *item)
{
auto p = painter();
ImageTestingItem *realItem = static_cast<ImageTestingItem*>(item);
auto actions = realItem->m_actions;
bool memDataUpdated = false;
if (actions.testFlag(ImageTestingItem::Action::Generate)) {
generateImage();
memDataUpdated = true;
}
if (actions.testFlag(ImageTestingItem::Action::RemoveAll)) {
int clearedImages = m_images.size();
if (clearedImages > 0) {
for (int i = 0; i < clearedImages; i++) {
auto image = m_images.takeFirst().image;
p->removeImage(image);
}
memDataUpdated = true;
}
}
if (actions.testFlag(ImageTestingItem::Action::RemoveHidden)) {
auto it = m_images.begin();
while (it != m_images.end()) {
if (!it->visible) {
p->removeImage(it->image);
it = m_images.erase(it);
} else {
it++;
}
}
memDataUpdated = true;
}
if (actions.testFlag(ImageTestingItem::Action::ShowHidden)) {
for (int i = 0; i < m_images.size(); i++)
m_images[i].visible = true;
}
if (actions.testFlag(ImageTestingItem::Action::RemoveNewest)) {
if (!m_images.isEmpty()) {
auto image = m_images.takeLast().image;
p->removeImage(image);
memDataUpdated = true;
}
}
if (actions.testFlag(ImageTestingItem::Action::HideNewest)) {
for (int i = m_images.size()-1; i >= 0; i--) {
if (m_images.at(i).visible) {
m_images[i].visible = false;
break;
}
}
}
if (actions.testFlag(ImageTestingItem::Action::CleanupResources)) {
p->cleanupResources();
memDataUpdated = true;
}
if (actions.testFlag(ImageTestingItem::Action::GenerateCanvas)) {
m_newCanvasPending += 1;
}
if (actions.testFlag(ImageTestingItem::Action::ReregisterCanvases)) {
m_reregisterPending = true;
}
if (actions.testFlag(ImageTestingItem::Action::UnregisterNewestCanvas)) {
if (!m_canvases.isEmpty()) {
p->removeImage(m_canvases.last().image);
m_canvases.last().image = {}; // now QCanvasImage::isNull() == true
}
}
if (actions.testFlag(ImageTestingItem::Action::RemoveNewestCanvas)) {
if (!m_canvases.isEmpty()) {
auto canvas = m_canvases.takeLast().canvas;
p->destroyCanvas(canvas);
}
}
m_showGradient = realItem->m_showGradient;
m_animateGradient = realItem->m_animateGradient;
// Update data values for the item
realItem->m_dataAmount = p->activeImageMemoryUsage();
realItem->dataAmountChanged();
realItem->m_imageAmount = p->activeImageCount();
realItem->imageAmountChanged();
if (memDataUpdated) {
// This is needed for cache amounts to update from the item side
QTimer::singleShot(0, realItem, [realItem]{realItem->update();});
}
realItem->m_actions = {};
}
void ImageTestingRenderer::prePaint(QCanvasPainter *painter)
{
if (m_reregisterPending) {
m_reregisterPending = false;
for (auto &canvas : m_canvases) {
if (canvas.image.isNull())
canvas.image = painter->addImage(canvas.canvas);
}
}
while (m_newCanvasPending > 0) {
const int canvasWidth = 1024;
const int canvasHeight = 1024;
QCanvasOffscreenCanvas canvas = painter->createCanvas({ canvasWidth, canvasHeight });
if (canvas.isNull())
qFatal("createCanvas() failed");
CanvasData canvasData;
canvasData.canvas = canvas;
canvasData.image = painter->addImage(canvas);
m_canvases << canvasData;
auto *rand = QRandomGenerator::global();
beginCanvasPainting(canvas);
painter->setFillStyle(qRgba(rand->generate() % 255, rand->generate() % 255, rand->generate() % 255, 255));
painter->fillRect({ 0, 0, canvasWidth, canvasHeight });
QFont font;
font.setPixelSize(40);
painter->setFont(font);
painter->setFillStyle(QColorConstants::Black);
painter->fillText(QString::asprintf("This is an offscreen canvas of pixel size %dx%d", canvasWidth, canvasHeight), 50, 500);
painter->fillText(QString::asprintf("using ca. %d KB", canvasData.image.sizeInBytes() / 1024), 50, 600);
endCanvasPainting();
m_newCanvasPending -= 1;
}
}
void ImageTestingRenderer::paint(QCanvasPainter *painter)
{
const float w = width();
const float h = height();
// Render all visible images
int imageAndCanvasCount = m_images.size() + m_canvases.size();
const float imageW = w * 0.5;
const float imageH = h * 0.5;
int index = 0;
painter->setTextAlign(QCanvasPainter::TextAlign::Center);
painter->setTextBaseline(QCanvasPainter::TextBaseline::Top);
QFont font;
float fontSize = imageH * 0.08;
font.setPixelSize(fontSize);
painter->setFont(font);
auto calculateRect = [=](int index) {
const float movPos = (float(index + 0.5) / imageAndCanvasCount - 0.5);
const float movX = imageW * movPos;
const float movY = imageH * movPos;
QRectF pos(w * 0.5 - imageW * 0.5 + movX,
h * 0.5 - imageH * 0.5 + movY,
imageW, imageH);
return pos;
};
for (auto &image : std::as_const(m_images)) {
if (image.visible) {
const QRectF pos = calculateRect(index);
painter->drawImage(image.image, pos);
painter->fillText(QStringLiteral("IMAGE INDEX: %1").arg(QString::number(index)), pos);
}
index++;
}
for (auto &canvas : std::as_const(m_canvases)) {
const QRectF pos = calculateRect(index);
painter->setStrokeStyle(QColorConstants::Red);
painter->setLineWidth(4);
painter->strokeRect(pos);
painter->drawImage(canvas.image, pos);
painter->fillText(QStringLiteral("CANVAS INDEX: %1").arg(QString::number(index - m_images.size())), pos);
index++;
}
static int anim = 0;
if (m_showGradient) {
float gradW = w * 0.8;
float gradH = h * 0.05;
float gradX = (w - gradW) * 0.5;
float gradY = 0;
QRectF rect(gradX, gradY, gradW, gradH);
QCanvasLinearGradient g(rect.x(), rect.y(), rect.x()+rect.width(), rect.y());
g.setColorAt(0.0f, QColorConstants::Black);
if (m_animateGradient)
anim++;
float gradPos = 0.5f + 0.5f * qSin(0.005 * anim);
g.setColorAt(gradPos, QColorConstants::Red);
g.setColorAt(1.0f, QColorConstants::Black);
painter->setFillStyle(g);
painter->fillRect(rect);
}
}
void ImageTestingRenderer::generateImage()
{
QImage image(1024, 1024, QImage::Format_RGBA8888);
image.fill(QColorConstants::Black);
auto *rand = QRandomGenerator::global();
int g = rand->generate() % 255;
int b = rand->generate() % 255;
int r = 0;
for (int y = 0; y < image.height(); y++) {
if (y % 10 == 0)
r = rand->generate() % 255;
for (int x = 0; x < image.width(); x++)
image.setPixel(x, y, qRgba(r, g, b, 100));
}
ImageData imageData;
imageData.image = painter()->addImage(image);
m_images << imageData;
}