Optimizations: motion blur is better, and quality is now customizable. Default value is 50%. which is again a good compromise.

app/qml/ApplicationSettings.qml

@@ -58,6 +58,7 @@ Item{
     property real bloom_strength: 0.65
 
     property real bloom_quality: 0.5
+    property real blur_quality: 0.5
 
     property real chroma_color: 0.0
     property real saturation_color: 0.0
@@ -168,7 +169,8 @@ Item{
             fontIndexes: fontIndexes,
             frameReflections: _frameReflections,
             showMenubar: showMenubar,
-            bloom_quality: bloom_quality
+            bloom_quality: bloom_quality,
+            blur_quality: blur_quality
         }
         return stringify(settings);
     }
@@ -243,6 +245,7 @@ Item{
         showMenubar = settings.showMenubar !== undefined ? settings.showMenubar : showMenubar;
 
         bloom_quality = settings.bloom_quality !== undefined ? settings.bloom_quality : bloom_quality;
+        blur_quality = settings.blur_quality !== undefined ? settings.blur_quality : blur_quality;
     }
 
     function loadProfileString(profileString){

app/qml/PreprocessedTerminal.qml

@@ -28,7 +28,8 @@ Item{
 
     property size virtualResolution: Qt.size(kterminal.width, kterminal.height)
     property alias mainTerminal: kterminal
-    property ShaderEffectSource mainSource: mBlur !== 0 ? blurredSourceLoader.item : kterminalSource
+    property ShaderEffectSource mainSource: kterminalSource
+    property ShaderEffectSource blurredSource: blurredSourceLoader.item
 
     property real scaleTexture: 1.0
     property alias title: ksession.title
@@ -41,9 +42,9 @@ Item{
 
     //The blur effect has to take into account the framerate
     property real mBlur: appSettings.motion_blur
-    property real motionBlurCoefficient: (_maxBlurCoefficient * mBlur + _minBlurCoefficient * (1 - mBlur))
+    property real motionBlurCoefficient: (_maxBlurCoefficient * Math.sqrt(mBlur) + _minBlurCoefficient * (1 - Math.sqrt(mBlur)))
     property real _minBlurCoefficient: 0.70
-    property real _maxBlurCoefficient: 0.90
+    property real _maxBlurCoefficient: 0.95
 
     property size terminalSize: kterminal.terminalSize
     property size fontMetrics: kterminal.fontMetrics
@@ -241,8 +242,8 @@ Item{
     Loader{
         id: blurredTerminalLoader
 
-        width: kterminalSource.textureSize.width
-        height: kterminalSource.textureSize.height
+        width: kterminal.width * scaleTexture * appSettings.blur_quality
+        height: kterminal.height * scaleTexture * appSettings.blur_quality
         active: mBlur !== 0
         asynchronous: true
 
@@ -268,13 +269,11 @@ Item{
 
                 "void main() {" +
                     "vec2 coords = qt_TexCoord0;" +
-                    "vec3 color = texture2D(txt_source, coords).rgb * 256.0;" +
+                    "vec3 origColor = texture2D(txt_source, coords).rgb;" +
+                    "vec3 blur_color = texture2D(blurredSource, coords).rgb * (1.0 - blurCoefficient);" +
+                    "vec3 color = min(origColor + blur_color, max(origColor, blur_color));" +
 
-                    "vec3 blur_color = texture2D(blurredSource, coords).rgb * 256.0;" +
-                    "blur_color = blur_color - blur_color * blurCoefficient;" +
-                    "color = step(vec3(1.0), color) * color + step(color, vec3(1.0)) * blur_color;" +
-
-                    "gl_FragColor = vec4(floor(color) / 256.0, 1.0);" +
+                    "gl_FragColor = vec4(color, step(0.004, rgb2grey(color - origColor)));" +
                 "}"
 
             onStatusChanged: if (log) console.log(log) //Print warning messages

app/qml/SettingsPerformanceTab.qml

@@ -83,6 +83,27 @@ Tab{
                 Text{text: Math.round(bloomSlider.value * 100) + "%"}
             }
         }
+        GroupBox{
+            title: qsTr("Motion Blur")
+            Layout.fillWidth: true
+            anchors.left: parent.left
+            anchors.right: parent.right
+            GridLayout{
+                id: blurQualityContainer
+                anchors.fill: parent
+
+                Text{text: qsTr("Blur Quality")}
+                Slider{
+                    Layout.fillWidth: true
+                    id: blurSlider
+                    onValueChanged: appSettings.blur_quality = value;
+                    value: appSettings.blur_quality
+                    stepSize: 0.10
+                    Component.onCompleted: minimumValue = 0.3 //Without this value gets set to 0.5
+                }
+                Text{text: Math.round(blurSlider.value * 100) + "%"}
+            }
+        }
         GroupBox{
             title: qsTr("Frame")
             Layout.fillWidth: true

app/qml/ShaderTerminal.qml

@@ -23,12 +23,15 @@ import QtGraphicalEffects 1.0
 
 ShaderEffect {
     property ShaderEffectSource source
+    property ShaderEffectSource blurredSource
     property ShaderEffectSource bloomSource
 
     property color font_color: appSettings.font_color
     property color background_color: appSettings.background_color
     property real bloom_strength: appSettings.bloom_strength * 2.5
 
+    property real motion_blur: appSettings.motion_blur
+
     property real jitter: appSettings.jitter * 0.007
     property real noise_strength: appSettings.noise_strength
     property size scaleNoiseSize: Qt.size((width) / (noiseTexture.width * appSettings.window_scaling * appSettings.fontScaling),
@@ -156,6 +159,8 @@ ShaderEffect {
         (bloom_strength !== 0 ? "
             uniform highp sampler2D bloomSource;
             uniform lowp float bloom_strength;" : "") +
+        (motion_blur !== 0 ? "
+            uniform sampler2D blurredSource;" : "") +
         (noise_strength !== 0 ? "
             uniform highp float noise_strength;" : "") +
         (((noise_strength !== 0 || jitter !== 0 || rgb_shift)
@@ -255,8 +260,14 @@ ShaderEffect {
                 color += randomPass(coords) * glowing_line_strength;" : "") +
 
 
-            "vec3 txt_color = texture2D(source, txt_coords).rgb;
-             float greyscale_color = rgb2grey(txt_color) + color;" +
+            "vec3 txt_color = texture2D(source, txt_coords).rgb;" +
+
+            (motion_blur !== 0 ? "
+                vec4 txt_blur = texture2D(blurredSource, txt_coords);
+                txt_color = txt_color + txt_blur.rgb * txt_blur.a;"
+            : "") +
+
+             "float greyscale_color = rgb2grey(txt_color) + color;" +
 
             (chroma_color !== 0 ?
                 (rgb_shift !== 0 ? "

app/qml/TerminalContainer.qml

@@ -11,6 +11,7 @@ ShaderTerminal{
     blending: false
 
     source: terminal.mainSource
+    blurredSource: terminal.blurredSource
     dispX: (12 / width) * appSettings.window_scaling
     dispY: (12 / height) * appSettings.window_scaling
     virtual_resolution: terminal.virtualResolution