66 lines
2.1 KiB
Go
66 lines
2.1 KiB
Go
package widget
|
|
|
|
import (
|
|
"github.com/go-gl/gl/all-core/gl"
|
|
)
|
|
|
|
// Filler is a widget that fills its box with a solid color
|
|
type Filler struct {
|
|
color [4]float32
|
|
}
|
|
|
|
// Fill creates a new Fill widget that fills its container with the specified color.
|
|
// The fill always fills to the edge of its box when calculated.
|
|
func Fill(red, green, blue, alpha float32) *Filler {
|
|
return &Filler{
|
|
color: [4]float32{red, green, blue, alpha},
|
|
}
|
|
}
|
|
|
|
// SetColor updates the fill color
|
|
func (f *Filler) SetColor(red, green, blue, alpha float32) {
|
|
f.color = [4]float32{red, green, blue, alpha}
|
|
}
|
|
|
|
// GetConstraints returns the size constraints for this Fill widget
|
|
func (f *Filler) GetConstraints() Constraints {
|
|
// Fill widgets always have flexible constraints to fill their container
|
|
return NewFlexConstraints(0, 0, 1e9, 1e9)
|
|
}
|
|
|
|
// Render implements the Widget interface for Fill
|
|
func (f *Filler) Render(ctx *Context, box *Box) (usedSize Size, err error) {
|
|
// Convert to OpenGL coordinates (bottom-left origin) from top-left origin
|
|
// Box Y is from top, convert to bottom-left
|
|
bottomY := float32(ctx.WindowHeight) - box.Position.Y - box.Size.Height
|
|
|
|
// Create vertices for the quad (exact pixel boundaries)
|
|
x1, y1 := box.Position.X, float32(ctx.WindowHeight)-box.Position.Y
|
|
x2, y2 := box.Position.X+box.Size.Width, float32(ctx.WindowHeight)-box.Position.Y
|
|
x3, y3 := box.Position.X+box.Size.Width, float32(ctx.WindowHeight)-box.Position.Y-box.Size.Height
|
|
x4, y4 := box.Position.X, float32(ctx.WindowHeight)-box.Position.Y-box.Size.Height
|
|
|
|
// Enable scissor test with proper boundaries to enforce clipping
|
|
// This prevents artifacts at the edges by ensuring rendering doesn't go beyond boundaries
|
|
gl.Scissor(
|
|
int32(box.Position.X),
|
|
int32(bottomY),
|
|
int32(box.Size.Width),
|
|
int32(box.Size.Height),
|
|
)
|
|
|
|
// Set the color
|
|
gl.Color4f(f.color[0], f.color[1], f.color[2], f.color[3])
|
|
|
|
// Draw using immediate mode
|
|
// The scissor test will clip these vertices to the exact boundaries
|
|
gl.Begin(gl.QUADS)
|
|
gl.Vertex2f(x1, y1)
|
|
gl.Vertex2f(x2, y2)
|
|
gl.Vertex2f(x3, y3)
|
|
gl.Vertex2f(x4, y4)
|
|
gl.End()
|
|
|
|
return box.Size, nil
|
|
}
|