File indexing completed on 2024-04-28 16:48:41

 /*
     SPDX-FileCopyrightText: 2022 Vlad Zahorodnii <vlad.zahorodnii@kde.org>
 
     SPDX-License-Identifier: GPL-2.0-or-later
 */
 
 #include "cursordelegate_opengl.h"
 #include "composite.h"
 #include "core/renderlayer.h"
 #include "core/rendertarget.h"
 #include "cursor.h"
 #include "kwingltexture.h"
 #include "kwinglutils.h"
 #include "scene/cursorscene.h"
 
 #include <cmath>
 
 namespace KWin
 {
 
 CursorDelegateOpenGL::~CursorDelegateOpenGL()
 {
 }
 
 void CursorDelegateOpenGL::paint(RenderTarget *renderTarget, const QRegion &region)
 {
     if (!region.intersects(layer()->mapToGlobal(layer()->rect()))) {
         return;
     }
 
     // Render the cursor scene in an offscreen render target.
     const QSize bufferSize = Cursors::self()->currentCursor()->rect().size() * renderTarget->devicePixelRatio();
     if (!m_texture || m_texture->size() != bufferSize) {
         m_texture = std::make_unique<GLTexture>(GL_RGBA8, bufferSize);
         m_framebuffer = std::make_unique<GLFramebuffer>(m_texture.get());
     }
 
     RenderTarget offscreenRenderTarget(m_framebuffer.get());
     offscreenRenderTarget.setDevicePixelRatio(renderTarget->devicePixelRatio());
 
     RenderLayer renderLayer(layer()->loop());
     renderLayer.setDelegate(std::make_unique<SceneDelegate>(Compositor::self()->cursorScene()));
     renderLayer.delegate()->prePaint();
     renderLayer.delegate()->paint(&offscreenRenderTarget, infiniteRegion());
     renderLayer.delegate()->postPaint();
 
     // Show the rendered cursor scene on the screen.
     const QRect cursorRect = layer()->mapToGlobal(layer()->rect());
     const qreal scale = renderTarget->devicePixelRatio();
 
     QMatrix4x4 mvp;
     mvp.ortho(QRect(QPoint(0, 0), renderTarget->size()));
     mvp.translate(std::round(cursorRect.x() * scale), std::round(cursorRect.y() * scale));
 
     GLFramebuffer *fbo = std::get<GLFramebuffer *>(renderTarget->nativeHandle());
     GLFramebuffer::pushFramebuffer(fbo);
 
     // Don't need to call GLVertexBuffer::beginFrame() and GLVertexBuffer::endOfFrame() because
     // the GLVertexBuffer::streamingBuffer() is not being used when painting cursor.
     glEnable(GL_BLEND);
     glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 
     m_texture->bind();
     ShaderBinder binder(ShaderTrait::MapTexture);
     binder.shader()->setUniform(GLShader::ModelViewProjectionMatrix, mvp);
     m_texture->render(region, QRect(0, 0, cursorRect.width(), cursorRect.height()), scale);
     m_texture->unbind();
     glDisable(GL_BLEND);
 
     GLFramebuffer::popFramebuffer();
 }
 
 } // namespace KWin