From 9f234899f5e2cbd51ee21b183370017099bc1226 Mon Sep 17 00:00:00 2001
From: Miikka Heikkinen <miikka.heikkinen@theqtcompany.com>
Date: Wed, 22 Apr 2015 11:52:36 +0300
Subject: [PATCH] Fix readPixels to work with custom framebuffer.
MIME-Version: 1.0
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ReadPixels always read from renderFbo if context had antialiasing
specified.
Also added buffer initialization to zero so pixels that fall outside
the framebuffer contain correct value.
Change-Id: I58b9fda18bc56a64346f83ccda575c758e9eaac5
Reviewed-by: Tomi Korpipää <tomi.korpipaa@theqtcompany.com>
Reviewed-by: Pasi Keränen <pasi.keranen@digia.com>
---
src/imports/qtcanvas3d/context3d.cpp | 7 ++-
.../canvas3d/tst_render_checkresult.js | 35 +++++++++--
.../canvas3d/tst_render_checkresult.qml | 63 ++++++++++++++++++-
3 files changed, 98 insertions(+), 7 deletions(-)
diff --git a/src/imports/qtcanvas3d/context3d.cpp b/src/imports/qtcanvas3d/context3d.cpp
index 38e0487..52777a5 100644
--- a/src/imports/qtcanvas3d/context3d.cpp
+++ b/src/imports/qtcanvas3d/context3d.cpp
@@ -5214,16 +5214,19 @@ void CanvasContext::readPixels(int x, int y, long width, long height, glEnums fo
return;
}
+ // Zero out the buffer (WebGL conformance requires pixels outside the framebuffer to be 0)
+ memset(bufferPtr, 0, width * height * 4);
+
// Check if the buffer is antialiased. If it is, we need to blit to the final buffer before
// reading the value.
- if (m_contextAttributes.antialias()) {
+ if (m_contextAttributes.antialias() && !m_currentFramebuffer) {
GLuint readFbo = m_canvas->resolveMSAAFbo();
glBindFramebuffer(GL_FRAMEBUFFER, readFbo);
}
glReadPixels(x, y, width, height, format, type, bufferPtr);
- if (m_contextAttributes.antialias())
+ if (m_contextAttributes.antialias() && !m_currentFramebuffer)
m_canvas->bindCurrentRenderTarget();
logAllGLErrors(__FUNCTION__);
diff --git a/tests/auto/qmltest/canvas3d/tst_render_checkresult.js b/tests/auto/qmltest/canvas3d/tst_render_checkresult.js
index 0eac410..94f2395 100644
--- a/tests/auto/qmltest/canvas3d/tst_render_checkresult.js
+++ b/tests/auto/qmltest/canvas3d/tst_render_checkresult.js
@@ -52,13 +52,13 @@ var textureCoordAttribute;
var vertexColorAttribute;
var colorFlagUniform;
+var customFbo;
function initializeGL(canvas) {
gl = canvas.getContext("");
gl.pixelStorei(gl.UNPACK_FLIP_Y_WEBGL, true);
var pixelRatio = canvas.devicePixelRatio;
gl.viewport(0, 0, pixelRatio * canvas.width, pixelRatio * canvas.height);
- gl.clearColor(1.0, 0.0, 0.0, 1.0);
initShaders();
initBuffers();
@@ -73,14 +73,29 @@ function initializeGL(canvas) {
}
function paintGL() {
+ gl.clearColor(1.0, 0.0, 0, 1.0);
gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
gl.drawElements(gl.TRIANGLES, 6, gl.UNSIGNED_SHORT, 0);
}
-function paintGL(x, y) {
- gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
+function paintGL(x, y, separateFbo) {
+ if (separateFbo) {
+ gl.bindFramebuffer(gl.FRAMEBUFFER, customFbo);
+ gl.clearColor(0.0, 1.0, 0.0, 1.0);
+ gl.clear(gl.COLOR_BUFFER_BIT);
+ } else {
+ gl.clearColor(1.0, 0.0, 0, 1.0);
+ gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
+ }
+
gl.drawElements(gl.TRIANGLES, 6, gl.UNSIGNED_SHORT, 0);
- return checkPixel(x, y);
+
+ var pixels = checkPixel(x, y);
+
+ if (separateFbo)
+ gl.bindFramebuffer(gl.FRAMEBUFFER, null);
+
+ return pixels;
}
function checkPixel(x, y) {
@@ -172,6 +187,18 @@ function initBuffers()
new Uint16Array([0, 1, 2,
0, 2, 3]),
gl.STATIC_DRAW);
+
+ // Custom framebuffer
+ customFbo = gl.createFramebuffer();
+ gl.bindFramebuffer(gl.FRAMEBUFFER, customFbo);
+ var texture = gl.createTexture();
+ gl.bindTexture(gl.TEXTURE_2D, texture);
+ gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.canvas.width, gl.canvas.height, 0, gl.RGBA,
+ gl.UNSIGNED_BYTE, null);
+ gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, texture, 0);
+
+ gl.bindFramebuffer(gl.FRAMEBUFFER, null);
+
}
function initShaders()
diff --git a/tests/auto/qmltest/canvas3d/tst_render_checkresult.qml b/tests/auto/qmltest/canvas3d/tst_render_checkresult.qml
index 350d2fd..935d1f7 100644
--- a/tests/auto/qmltest/canvas3d/tst_render_checkresult.qml
+++ b/tests/auto/qmltest/canvas3d/tst_render_checkresult.qml
@@ -54,6 +54,7 @@ Item {
property int blue: -1
property int alpha: -1
property bool renderOk: false
+ property bool separateFbo: false
Canvas3D {
id: render_check_result
@@ -62,7 +63,7 @@ Item {
onInitializeGL: Content.initializeGL(this)
onPaintGL: {
if (checkResult) {
- pixels = Content.paintGL(xpos, ypos)
+ pixels = Content.paintGL(xpos, ypos, separateFbo)
red = pixels[0]
green = pixels[1]
blue = pixels[2]
@@ -89,6 +90,7 @@ Item {
ypos = 150
checkResult = true
renderOk = false
+ separateFbo = false
waitForRendering(render_check_result)
tryCompare(top, "renderOk", true)
tryCompare(top, "red", 0x00)
@@ -123,6 +125,7 @@ Item {
ypos = 150
checkResult = true
renderOk = false
+ separateFbo = false
waitForRendering(render_check_result)
tryCompare(top, "renderOk", true)
tryCompare(render_check_result, "textureLoaded", true, 10000)
@@ -144,6 +147,7 @@ Item {
ypos = 150
checkResult = true
renderOk = false
+ separateFbo = false
waitForRendering(render_check_result)
tryCompare(top, "renderOk", true)
tryCompare(top, "red", 0x22)
@@ -154,5 +158,62 @@ Item {
waitForRendering(render_check_result)
}
+
+ function test_render_4_checkresult() {
+ // Render to separate FBO.
+ waitForRendering(render_check_result)
+ Content.setColor(0x40, 0x60, 0x80, 0xff)
+
+ // Check color in the center of the square
+ xpos = 150
+ ypos = 150
+ checkResult = true
+ renderOk = false
+ separateFbo = true
+ waitForRendering(render_check_result)
+ tryCompare(top, "renderOk", true)
+ tryCompare(top, "red", 0x40)
+ tryCompare(top, "green", 0x60)
+ tryCompare(top, "blue", 0x80)
+ tryCompare(top, "alpha", 0xff)
+ checkResult = false
+
+ waitForRendering(render_check_result)
+
+ // Check color in the corner of the screen, which is cleared with green
+ xpos = 0
+ ypos = 0
+ checkResult = true
+ renderOk = false
+ waitForRendering(render_check_result)
+ tryCompare(top, "renderOk", true)
+ tryCompare(top, "red", 0x00)
+ tryCompare(top, "green", 0xff)
+ tryCompare(top, "blue", 0x00)
+ tryCompare(top, "alpha", 0xff)
+ checkResult = false
+
+ waitForRendering(render_check_result)
+ }
+
+ function test_render_5_checkresult() {
+ // Check that pixels outside framebuffer are zero
+ waitForRendering(render_check_result)
+ Content.setColor(0x22, 0x99, 0xff, 0x80)
+ xpos = 9999
+ ypos = 9999
+ checkResult = true
+ renderOk = false
+ separateFbo = false
+ waitForRendering(render_check_result)
+ tryCompare(top, "renderOk", true)
+ tryCompare(top, "red", 0x0)
+ tryCompare(top, "green", 0x0)
+ tryCompare(top, "blue", 0x0)
+ tryCompare(top, "alpha", 0x0)
+ checkResult = false
+
+ waitForRendering(render_check_result)
+ }
}
}
--
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