@x1 : The Linear Gradient Start X Coordinate Attribute

The x1 attribute defines the X-coordinate of the starting point for a linear gradient vector. Together with y1, it establishes the origin point from which the gradient begins, determining both the angle and direction of the color transition.

Usage

The x1 attribute is used to:

Define the horizontal starting position of a linear gradient
Control gradient angle when combined with x2/y2
Support both relative (percentage) and absolute (unit-based) coordinates
Enable dynamic gradient positioning through data binding
Work with both objectBoundingBox (default) and userSpaceOnUse coordinate systems
Create horizontal, vertical, diagonal, or custom-angle gradients
Position gradients precisely for data visualizations and charts

<svg xmlns="http://www.w3.org/2000/svg" width="400" height="200">
    <defs>
        <linearGradient id="myGradient" x1="0%" y1="0%" x2="100%" y2="0%">
            <stop offset="0%" stop-color="#3498db" />
            <stop offset="100%" stop-color="#e74c3c" />
        </linearGradient>
    </defs>
    <rect x="10" y="10" width="380" height="180" fill="url(#myGradient)" />
</svg>

Supported Values

Value Type	Format	Description	Example
Percentage	`0%` to `100%`	Relative to shape bounding box (objectBoundingBox mode)	`x1="0%"`
Decimal	`0` to `1.0`	Relative coordinate (0=left, 1=right)	`x1="0.5"`
Length Units	`pt`, `px`, `mm`, `cm`, `in`	Absolute coordinates (userSpaceOnUse mode)	`x1="50pt"`
Default	`0%`	Used when attribute is omitted	-

Common Patterns

<!-- Left edge (default) -->
<linearGradient id="g1" x1="0%">

<!-- Center -->
<linearGradient id="g2" x1="50%">

<!-- Right edge -->
<linearGradient id="g3" x1="100%">

<!-- Absolute positioning -->
<linearGradient id="g4" x1="100pt" gradientUnits="userSpaceOnUse">

Supported Elements

The x1 attribute is supported on:

<linearGradient> - Defines linear gradient start X position

Note: This attribute is NOT used with <radialGradient> elements, which use cx/cy and fx/fy instead.

Data Binding

Dynamic Gradient Start Position

Bind the x1 coordinate to data values for dynamic gradient positioning:

<!-- Model: { startX: 25 } -->
<svg width="400" height="100">
    <defs>
        <linearGradient id="dynamicStart"
                        x1="%" y1="0%"
                        x2="100%" y2="0%">
            <stop offset="0%" stop-color="#3498db" />
            <stop offset="100%" stop-color="#e74c3c" />
        </linearGradient>
    </defs>
    <rect width="400" height="100" fill="url(#dynamicStart)" />
</svg>

Calculated Gradient Angles

Calculate x1/x2 coordinates to create specific gradient angles:

<!-- Model: { angle: 45 } -->
<!-- Calculates gradient vector from angle in degrees -->
<svg width="400" height="200">
    <defs>
        <linearGradient id="angleGrad"
                        x1="%"
                        y1="%"
                        x2="%"
                        y2="%">
            <stop offset="0%" stop-color="#9b59b6" />
            <stop offset="100%" stop-color="#3498db" />
        </linearGradient>
    </defs>
    <rect width="400" height="200" fill="url(#angleGrad)" />
</svg>

Data-Driven Chart Gradients

Position gradients based on data ranges:

<!-- Model: { dataMin: 0, dataMax: 100, highlightStart: 30 } -->
<svg width="500" height="300">
    <defs>
        <linearGradient id="chartGrad"
                        x1="%"
                        y1="0%"
                        x2="100%"
                        y2="0%">
            <stop offset="0%" stop-color="#f39c12" />
            <stop offset="100%" stop-color="#e74c3c" />
        </linearGradient>
    </defs>
    <rect x="0" y="0" width="500" height="300" fill="url(#chartGrad)" />
</svg>

Conditional Gradient Direction

Change gradient direction based on data conditions:

<!-- Model: { direction: "rtl", value: 75 } -->
<svg width="400" height="100">
    <defs>
        <linearGradient id="dirGrad"
                        x1=""
                        y1="0%"
                        x2=""
                        y2="0%">
            <stop offset="0%" stop-color="#2ecc71" />
            <stop offset="100%" stop-color="#27ae60" />
        </linearGradient>
    </defs>
    <rect width="" height="100" fill="url(#dirGrad)" />
</svg>

Responsive Gradient Positioning

Adjust gradient based on viewport or container size:

<!-- Model: { containerWidth: 800, offset: 200 } -->
<svg width="" height="200">
    <defs>
        <linearGradient id="responsive"
                        x1="%"
                        y1="0%"
                        x2="100%"
                        y2="0%"
                        gradientUnits="objectBoundingBox">
            <stop offset="0%" stop-color="#3498db" />
            <stop offset="100%" stop-color="#9b59b6" />
        </linearGradient>
    </defs>
    <rect width="" height="200" fill="url(#responsive)" />
</svg>

Notes

Coordinate Systems

The x1 attribute behaves differently based on gradientUnits:

objectBoundingBox (default): Relative to filled shape
- Values 0-1 or 0%-100%
- 0% = left edge, 50% = center, 100% = right edge
- Gradient automatically scales with shape size
- Most common for responsive designs
userSpaceOnUse: Absolute document coordinates
- Values in pt, px, mm, cm, in
- Fixed position in document space
- Useful for consistent gradients across multiple shapes

Gradient Vector Direction

The gradient vector is defined by start point (x1, y1) and end point (x2, y2):

<!-- Horizontal (left to right) - DEFAULT -->
<linearGradient x1="0%" y1="0%" x2="100%" y2="0%">

<!-- Horizontal (right to left) -->
<linearGradient x1="100%" y1="0%" x2="0%" y2="0%">

<!-- Diagonal (top-left to bottom-right) -->
<linearGradient x1="0%" y1="0%" x2="100%" y2="100%">

<!-- Custom angle: 45 degrees from center -->
<linearGradient x1="25%" y1="75%" x2="75%" y2="25%">

Default Behavior

Default value: 0% (left edge)
Default gradient: horizontal left-to-right (x1=”0%”, y1=”0%”, x2=”100%”, y2=”0%”)
Must be used with <linearGradient> only

Performance Considerations

Percentage values are more efficient than calculations
Static gradients perform better than data-bound gradients
Consider caching calculated gradient definitions
Use CSS variables for frequently changed values

Examples

Basic Horizontal Gradient (Default)

<svg width="400" height="100">
    <defs>
        <linearGradient id="horizontal" x1="0%" y1="0%" x2="100%" y2="0%">
            <stop offset="0%" stop-color="#3498db" />
            <stop offset="100%" stop-color="#e74c3c" />
        </linearGradient>
    </defs>
    <rect width="400" height="100" fill="url(#horizontal)" />
</svg>

Gradient Starting from Center

<svg width="400" height="100">
    <defs>
        <linearGradient id="centerStart" x1="50%" y1="0%" x2="100%" y2="0%">
            <stop offset="0%" stop-color="#ffffff" />
            <stop offset="100%" stop-color="#3498db" />
        </linearGradient>
    </defs>
    <rect width="400" height="100" fill="url(#centerStart)" />
</svg>

Reverse Horizontal Gradient

<svg width="400" height="100">
    <defs>
        <linearGradient id="reverse" x1="100%" y1="0%" x2="0%" y2="0%">
            <stop offset="0%" stop-color="#e74c3c" />
            <stop offset="100%" stop-color="#3498db" />
        </linearGradient>
    </defs>
    <rect width="400" height="100" fill="url(#reverse)" />
</svg>

Diagonal Gradient with Custom Start

<svg width="400" height="300">
    <defs>
        <linearGradient id="diagonal" x1="20%" y1="20%" x2="80%" y2="80%">
            <stop offset="0%" stop-color="#9b59b6" />
            <stop offset="100%" stop-color="#3498db" />
        </linearGradient>
    </defs>
    <rect width="400" height="300" fill="url(#diagonal)" />
</svg>

Bar Chart with Gradient Fill

<svg width="500" height="300">
    <defs>
        <linearGradient id="barGrad" x1="0%" y1="0%" x2="0%" y2="100%">
            <stop offset="0%" stop-color="#3498db" />
            <stop offset="100%" stop-color="#2c3e50" />
        </linearGradient>
    </defs>

    <!-- Chart bars -->
    <rect x="50" y="100" width="60" height="180" fill="url(#barGrad)" />
    <rect x="130" y="50" width="60" height="230" fill="url(#barGrad)" />
    <rect x="210" y="120" width="60" height="160" fill="url(#barGrad)" />
    <rect x="290" y="80" width="60" height="200" fill="url(#barGrad)" />
    <rect x="370" y="140" width="60" height="140" fill="url(#barGrad)" />
</svg>

Progress Bar with Left-to-Right Gradient

<svg width="400" height="50">
    <defs>
        <linearGradient id="progress" x1="0%" y1="0%" x2="100%" y2="0%">
            <stop offset="0%" stop-color="#2ecc71" />
            <stop offset="50%" stop-color="#27ae60" />
            <stop offset="100%" stop-color="#229954" />
        </linearGradient>
    </defs>

    <rect x="0" y="0" width="400" height="50" rx="25" fill="#ecf0f1" />
    <rect x="0" y="0" width="280" height="50" rx="25" fill="url(#progress)" />
</svg>

Status Badge with Gradient

<svg width="150" height="50">
    <defs>
        <linearGradient id="badge" x1="0%" y1="0%" x2="100%" y2="0%">
            <stop offset="0%" stop-color="#27ae60" />
            <stop offset="100%" stop-color="#2ecc71" />
        </linearGradient>
    </defs>

    <rect width="150" height="50" rx="25" fill="url(#badge)" />
    <text x="75" y="32" text-anchor="middle" fill="white" font-size="16" font-weight="bold">
        Active
    </text>
</svg>

Gauge Chart with Angular Gradient

<svg width="300" height="200" viewBox="0 0 300 200">
    <defs>
        <linearGradient id="gauge" x1="0%" y1="100%" x2="100%" y2="0%">
            <stop offset="0%" stop-color="#2ecc71" />
            <stop offset="50%" stop-color="#f39c12" />
            <stop offset="100%" stop-color="#e74c3c" />
        </linearGradient>
    </defs>

    <path d="M 50,150 A 100,100 0 0,1 250,150"
          fill="none" stroke="url(#gauge)" stroke-width="30" stroke-linecap="round" />
</svg>

Heatmap Legend with Horizontal Gradient

<svg width="400" height="80">
    <defs>
        <linearGradient id="heatmap" x1="0%" y1="0%" x2="100%" y2="0%">
            <stop offset="0%" stop-color="#2ecc71" />
            <stop offset="25%" stop-color="#f1c40f" />
            <stop offset="50%" stop-color="#e67e22" />
            <stop offset="75%" stop-color="#e74c3c" />
            <stop offset="100%" stop-color="#c0392b" />
        </linearGradient>
    </defs>

    <rect x="10" y="30" width="380" height="20" fill="url(#heatmap)" />
    <text x="10" y="20" font-size="12">Low</text>
    <text x="360" y="20" font-size="12">High</text>
</svg>

Card Header with Gradient Background

<svg width="400" height="120">
    <defs>
        <linearGradient id="cardHeader" x1="0%" y1="0%" x2="100%" y2="0%">
            <stop offset="0%" stop-color="#667eea" />
            <stop offset="100%" stop-color="#764ba2" />
        </linearGradient>
    </defs>

    <rect width="400" height="120" rx="8" fill="url(#cardHeader)" />
    <text x="20" y="50" fill="white" font-size="28" font-weight="bold">
        Sales Dashboard
    </text>
    <text x="20" y="85" fill="white" font-size="14" opacity="0.9">
        Q4 2024 Performance
    </text>
</svg>

Data Visualization Area Fill

<svg width="500" height="300">
    <defs>
        <linearGradient id="areaFill" x1="0%" y1="0%" x2="0%" y2="100%">
            <stop offset="0%" stop-color="#3498db" stop-opacity="0.8" />
            <stop offset="100%" stop-color="#3498db" stop-opacity="0.1" />
        </linearGradient>
    </defs>

    <path d="M 0,250 L 50,200 L 100,150 L 150,120 L 200,100 L 250,130 L 300,110 L 350,140 L 400,120 L 450,90 L 500,110 L 500,300 L 0,300 Z"
          fill="url(#areaFill)" />
</svg>

Button with Horizontal Gradient

<svg width="200" height="60">
    <defs>
        <linearGradient id="buttonGrad" x1="0%" y1="0%" x2="100%" y2="0%">
            <stop offset="0%" stop-color="#3498db" />
            <stop offset="50%" stop-color="#2980b9" />
            <stop offset="100%" stop-color="#3498db" />
        </linearGradient>
    </defs>

    <rect width="200" height="60" rx="8" fill="url(#buttonGrad)" />
    <text x="100" y="38" text-anchor="middle" fill="white" font-size="18" font-weight="bold">
        Submit
    </text>
</svg>

Data-Driven Gradient Start

<!-- Model: { highlightPosition: 30, color1: "#3498db", color2: "#e74c3c" } -->
<svg width="400" height="100">
    <defs>
        <linearGradient id="dataStart"
                        x1="%"
                        y1="0%"
                        x2="100%"
                        y2="0%">
            <stop offset="0%" stop-color="" />
            <stop offset="100%" stop-color="" />
        </linearGradient>
    </defs>
    <rect width="400" height="100" fill="url(#dataStart)" />
</svg>

Striped Pattern with Offset Start

<svg width="400" height="100">
    <defs>
        <linearGradient id="stripes" x1="0%" y1="0%" x2="10%" y2="0%" spreadMethod="repeat">
            <stop offset="0%" stop-color="#3498db" />
            <stop offset="50%" stop-color="#2980b9" />
            <stop offset="100%" stop-color="#3498db" />
        </linearGradient>
    </defs>
    <rect width="400" height="100" fill="url(#stripes)" />
</svg>

Multi-Bar Chart with Shared Gradient

<svg width="600" height="400">
    <defs>
        <linearGradient id="barGradient" x1="0%" y1="0%" x2="0%" y2="100%">
            <stop offset="0%" stop-color="#3498db" />
            <stop offset="100%" stop-color="#1a5490" />
        </linearGradient>
    </defs>

    <!-- Sales by region -->
    <rect x="50" y="150" width="80" height="220" fill="url(#barGradient)" />
    <text x="90" y="390" text-anchor="middle" font-size="12">North</text>

    <rect x="170" y="100" width="80" height="270" fill="url(#barGradient)" />
    <text x="210" y="390" text-anchor="middle" font-size="12">South</text>

    <rect x="290" y="180" width="80" height="190" fill="url(#barGradient)" />
    <text x="330" y="390" text-anchor="middle" font-size="12">East</text>

    <rect x="410" y="130" width="80" height="240" fill="url(#barGradient)" />
    <text x="450" y="390" text-anchor="middle" font-size="12">West</text>
</svg>