diff --git a/src/imports/qtcanvas3d/canvas3d.cpp b/src/imports/qtcanvas3d/canvas3d.cpp
index bd1ff562e98fc6f44f50f031e1960026afa52131..e47a20c500880536d942f7b15b7d78fc383a040f 100644
--- a/src/imports/qtcanvas3d/canvas3d.cpp
+++ b/src/imports/qtcanvas3d/canvas3d.cpp
@@ -243,7 +243,6 @@ QJSValue Canvas::getContext(const QString &type, const QVariantMap &options)
// Ensure ignored attributes are left to their default state
m_contextAttribs.setPremultipliedAlpha(false);
- m_contextAttribs.setPreserveDrawingBuffer(false);
m_contextAttribs.setPreferLowPowerToHighPerformance(false);
m_contextAttribs.setFailIfMajorPerformanceCaveat(false);
}
@@ -846,6 +845,20 @@ void Canvas::renderNext()
<< m_displayFbo->texture()
<< " from FBO:" << m_displayFbo->handle();
+ if (m_contextAttribs.preserveDrawingBuffer()) {
+ // Copy the content of display fbo to the render fbo
+ GLint texBinding2D;
+ glGetIntegerv(GL_TEXTURE_BINDING_2D, &texBinding2D);
+
+ m_displayFbo->bind();
+ glBindTexture(GL_TEXTURE_2D, m_renderFbo->texture());
+
+ glCopyTexImage2D(GL_TEXTURE_2D, 0, m_displayFbo->format().internalTextureFormat(),
+ 0, 0, m_fboSize.width(), m_fboSize.height(), 0);
+
+ glBindTexture(GL_TEXTURE_2D, texBinding2D);
+ }
+
// FBO ids and texture id's have been generated, we can now free the old display FBO
delete m_oldDisplayFbo;
m_oldDisplayFbo = 0;
diff --git a/tests/auto/qmltest/canvas3d/tst_render_preserve.js b/tests/auto/qmltest/canvas3d/tst_render_preserve.js
new file mode 100644
index 0000000000000000000000000000000000000000..f2cbe4400bc1d1379c4b1aa127d2ce7b636102cd
--- /dev/null
+++ b/tests/auto/qmltest/canvas3d/tst_render_preserve.js
@@ -0,0 +1,153 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the QtCanvas3D module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL3$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPLv3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or later as published by the Free
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+var gl;
+
+var colorBuffer;
+
+var vertexPositionAttribute;
+var vertexColorAttribute;
+
+var vertexBuffer;
+
+function initializeGL(canvas) {
+ gl = canvas.getContext("", {preserveDrawingBuffer:true});
+ gl.pixelStorei(gl.UNPACK_FLIP_Y_WEBGL, true);
+ var pixelRatio = canvas.devicePixelRatio;
+ gl.viewport(0, 0, pixelRatio * canvas.width, pixelRatio * canvas.height);
+
+ initShaders();
+ initBuffers();
+}
+
+function paintGL() {
+ gl.clearColor(1.0, 0.0, 0.0, 1.0);
+ gl.clear(gl.COLOR_BUFFER_BIT);
+ gl.drawArrays(gl.TRIANGLES, 0, 3);
+}
+
+function checkPixel(x, y) {
+ var pixels = new Uint8Array(4);
+ gl.readPixels(x, y, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, pixels);
+ return pixels;
+}
+
+function setColor(r, g, b, a) {
+ gl.bindBuffer(gl.ARRAY_BUFFER, colorBuffer);
+ var colors = [r / 255.0, g / 255.0, b / 255.0, a / 255.0];
+ var generatedColors = [];
+ for (var i = 0; i < 4; i++)
+ generatedColors = generatedColors.concat(colors);
+ gl.bufferData(gl.ARRAY_BUFFER,
+ new Float32Array(generatedColors),
+ gl.STATIC_DRAW);
+ gl.enableVertexAttribArray(vertexColorAttribute);
+ gl.vertexAttribPointer(vertexColorAttribute, 4, gl.FLOAT, false, 0, 0);
+}
+
+function initBuffers()
+{
+ vertexBuffer = gl.createBuffer();
+ gl.bindBuffer(gl.ARRAY_BUFFER, vertexBuffer);
+ gl.bufferData(
+ gl.ARRAY_BUFFER, new Float32Array(
+ [-1.0, -1.0,
+ 1.0, -1.0,
+ -1.0, 1.0
+ ]),
+ gl.STATIC_DRAW);
+
+ gl.bindBuffer(gl.ARRAY_BUFFER, vertexBuffer);
+ gl.vertexAttribPointer(vertexPositionAttribute, 2, gl.FLOAT, false, 0, 0);
+ gl.enableVertexAttribArray(vertexPositionAttribute);
+
+ colorBuffer = gl.createBuffer();
+ setColor(0.0, 0.0, 255.0, 255.0);
+}
+
+function initShaders()
+{
+ var vertexShader = getShader(
+ gl,
+ "attribute highp vec2 aVertexPosition; \
+ attribute mediump vec4 aVertexColor; \
+ varying mediump vec4 vColor; \
+ void main(void) { \
+ gl_Position = vec4(aVertexPosition, 0.0, 1.0); \
+ vColor = aVertexColor; \
+ }",
+ gl.VERTEX_SHADER);
+ var fragmentShader = getShader(
+ gl,
+ "varying mediump vec4 vColor; \
+ void main(void) { \
+ gl_FragColor = vColor; \
+ }",
+ gl.FRAGMENT_SHADER);
+
+ var shaderProgram = gl.createProgram();
+ gl.attachShader(shaderProgram, vertexShader);
+ gl.attachShader(shaderProgram, fragmentShader);
+ gl.linkProgram(shaderProgram);
+ gl.deleteShader(vertexShader);
+ gl.deleteShader(fragmentShader);
+
+ if (!gl.getProgramParameter(shaderProgram, gl.LINK_STATUS)) {
+ console.log("Could not initialize shaders");
+ console.log(gl.getProgramInfoLog(shaderProgram));
+ }
+
+ gl.useProgram(shaderProgram);
+
+ vertexPositionAttribute = gl.getAttribLocation(shaderProgram, "aVertexPosition");
+ gl.enableVertexAttribArray(vertexPositionAttribute);
+ vertexColorAttribute = gl.getAttribLocation(shaderProgram, "aVertexColor");
+ gl.enableVertexAttribArray(vertexColorAttribute);
+}
+
+function getShader(gl, str, type) {
+ var shader = gl.createShader(type);
+ gl.shaderSource(shader, str);
+ gl.compileShader(shader);
+
+ if (!gl.getShaderParameter(shader, gl.COMPILE_STATUS)) {
+ console.log("JS:Shader compile failed");
+ console.log(gl.getShaderInfoLog(shader));
+ return null;
+ }
+
+ return shader;
+}
diff --git a/tests/auto/qmltest/canvas3d/tst_render_preserve.qml b/tests/auto/qmltest/canvas3d/tst_render_preserve.qml
new file mode 100644
index 0000000000000000000000000000000000000000..5a1c25737dfa6f2a6c21d17ff2e7150110b470b9
--- /dev/null
+++ b/tests/auto/qmltest/canvas3d/tst_render_preserve.qml
@@ -0,0 +1,141 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the QtCanvas3D module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL3$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPLv3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or later as published by the Free
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+import QtQuick 2.2
+import QtCanvas3D 1.0
+import QtTest 1.0
+
+import "tst_render_preserve.js" as Content
+
+Item {
+ id: top
+ height: 300
+ width: 300
+
+ property int xpos: 0
+ property int ypos: 0
+ property var pixels
+ property int red: -1
+ property int green: -1
+ property int blue: -1
+ property int alpha: -1
+ property bool paintDone: true
+ property bool checkDone: true
+ property bool initDone: false
+
+ Canvas3D {
+ id: render_preserve
+ property bool textureLoaded: false
+ anchors.fill: parent
+ onInitializeGL: {
+ Content.initializeGL(this)
+ initDone = true
+ }
+ onPaintGL: {
+ if (!paintDone) {
+ Content.paintGL()
+ paintDone = true
+ }
+
+ if (!checkDone) {
+ pixels = Content.checkPixel(xpos, ypos)
+ red = pixels[0]
+ green = pixels[1]
+ blue = pixels[2]
+ alpha = pixels[3]
+ delete pixels
+ checkDone = true
+ }
+ }
+ }
+
+ TestCase {
+ name: "Canvas3D_render_preserve"
+ when: windowShown
+
+ function test_render_1_preserve() {
+ tryCompare(top, "initDone", true)
+ Content.setColor(0x00, 0x00, 0xff, 0xff)
+ // Draw the frame exactly once. That way one of the framebuffers has our scene and
+ // the other is default empty.
+ paintDone = false;
+ tryCompare(top, "paintDone", true)
+
+ // We cannot control if we are reading from the first or second framebuffer, since we
+ // cannot actually reliably sync with the render loop. We work around this issue
+ // by doing the pixel checks multiple times. That way at least one of the checks
+ // is likely to target the framebuffer we didn't draw our frame to, and therefore
+ // fails if the preserve is not working.
+ for (var i = 0; i < 10; i++) {
+ // Check color in the left side (part of the triangle)
+ xpos = 75
+ ypos = 150
+ checkDone = false
+ tryCompare(top, "checkDone", true)
+ compare(top.red, 0x00)
+ compare(top.green, 0x00)
+ compare(top.blue, 0xff)
+ compare(top.alpha, 0xff)
+
+ // Check color in the right part of the screen, which is cleared with red
+ xpos = 225
+ ypos = 150
+ checkDone = false
+ tryCompare(top, "checkDone", true)
+ compare(top.red, 0xff)
+ compare(top.green, 0x00)
+ compare(top.blue, 0x00)
+ compare(top.alpha, 0xff)
+ }
+
+ Content.setColor(0x00, 0xcc, 0x00, 0xff)
+ paintDone = false;
+ tryCompare(top, "paintDone", true)
+
+ for (var j = 0; j < 10; j++) {
+ // Check color in the left side (part of the triangle)
+ xpos = 75
+ ypos = 150
+ checkDone = false
+ tryCompare(top, "checkDone", true)
+ compare(top.red, 0x00)
+ compare(top.green, 0xcc)
+ compare(top.blue, 0x00)
+ compare(top.alpha, 0xff)
+ }
+ }
+ }
+}