Lines¶

Inherits: Object
C++ type: Lines

Description¶

Renders a collection of 3D line segments. Useful for debug overlays, grids, trajectory paths, and other wireframe visuals. Each line is defined by two endpoints and an optional per-endpoint colour for gradient lines.

The Lines object maintains an internal dynamic buffer. Call updateLines() after modifying line data to upload changes to the GPU.

Properties¶

Methods¶

Property details¶

maxLines¶

• Setter: void setMaxLines(unsigned int maxLines)
• Getter: unsigned int getMaxLines() const

Pre-allocates buffer space for this many lines. Resize before calling load() for best performance.

Method details¶

load¶

• bool load()

Explicitly initialises the GPU buffer. This method is C++ only and is normally optional because the render system initialises lines automatically.

addLine¶

Several overloads are available:

• void addLine(LineData line)
• void addLine(Vector3 pointA, Vector3 pointB)
• void addLine(Vector3 pointA, Vector3 pointB, Vector3 color)
• void addLine(Vector3 pointA, Vector3 pointB, Vector4 color)
• void addLine(Vector3 pointA, Vector3 pointB, Vector4 colorA, Vector4 colorB)

Adds a new line segment. The last overload lets each endpoint have a different colour.

Lines debug(&scene);
debug.load();
debug.addLine(Vector3(0,0,0), Vector3(1,0,0), Vector4(1,0,0,1));  // red X axis
debug.addLine(Vector3(0,0,0), Vector3(0,1,0), Vector4(0,1,0,1));  // green Y axis
debug.addLine(Vector3(0,0,0), Vector3(0,0,1), Vector4(0,0,1,1));  // blue Z axis
debug.updateLines();

local debug = Lines(scene)
debug:addLine(Vector3(0,0,0), Vector3(1,0,0), Vector4(1,0,0,1))
debug:addLine(Vector3(0,0,0), Vector3(0,1,0), Vector4(0,1,0,1))
debug:addLine(Vector3(0,0,0), Vector3(0,0,1), Vector4(0,0,1,1))
debug:updateLines()

getLine¶

• LineData& getLine(size_t index)

Returns a reference to the LineData at the given index. Modify in-place then call updateLines().

updateLine¶

• void updateLine(size_t index, ...)

Overwrites an existing line's endpoints and/or colour. Multiple overloads mirror addLine(). Call updateLines() afterwards.

removeLine¶

• void removeLine(size_t index)

Removes the line at index. All subsequent indices shift down.

updateLines¶

• void updateLines()

Uploads all pending line changes to the GPU. Must be called after any addLine, updateLine, or removeLine call.

getNumLines¶

• size_t getNumLines()

Returns the current number of line segments.

clearLines¶

• void clearLines()

Removes all line segments.

customShader¶

• Setter: void setCustomShader(const std::string& path)
• Getter: std::string getCustomShader() const

Project-relative base path of a forked shader ("shaders/laser" resolves to shaders/laser.vert and shaders/laser.frag, or "a.vert|b.frag" names the files separately). Empty (default) uses the scene default shader for this type, or the engine built-in. Changing it reloads the component. Same semantics as Mesh.customShader; see Custom Shaders.

setShaderUniform¶

• void setShaderUniform(const std::string& name, const Vector4& value)
• void setShaderUniform(const std::string& name, const Vector3& value)
• void setShaderUniform(const std::string& name, const Vector2& value)
• void setShaderUniform(const std::string& name, float value)
• Vector4 getShaderUniform(const std::string& name) const
• bool removeShaderUniform(const std::string& name)

Values for the members of the custom shader's u_vs_customParams / u_fs_customParams blocks, by member name. Setting a value only rewrites the uploaded block, so it can run every frame; a member with no value reads zero, or the scene's value under a scene default shader, and time (seconds since startup) and resolution (render target size) are reserved for the engine. Same semantics as Mesh.setShaderUniform; see Custom Shaders — Shader uniforms.

lines.setCustomShader("shaders/laser");
lines.setShaderUniform("strength", 0.8f);
lines.setShaderUniform("glowColor", Vector4(1.0f, 0.8f, 0.2f, 1.0f));

lines.customShader = "shaders/laser"
lines:setShaderUniform("strength", 0.8)
lines:setShaderUniform("glowColor", Vector4(1, 0.8, 0.2, 1))