Noah Petherbridge
5434484b6e
The `level.Canvas` is a widget that holds onto its Palette and Grid and has interactions to allow scrolling and editing the grid using the swatches available on the palette. Thus all of the logic in the Editor Mode for drawing directly onto the root SDL surface are now handled inside a level.Canvas instance. The `level.Canvas` widget has the following properties: * Like any widget it has an X,Y position and a width/height. * It has a Scroll position to control which slice of its drawing will be visible inside its bounding box. * It supports levels having negative coordinates for their pixels. It doesn't care. The default Scroll position is (0,0) at the top left corner of the widget but you can scroll into the negatives and see the negative pixels. * Keyboard keys will scroll the viewport inside the canvas. * The canvas draws only the pixels that are visible inside its bounding box. This feature will eventually pave the way toward: * Doodads being dropped on top of your map, each Doodad being its own Canvas widget. * Using drawings as button icons for the user interface, as the Canvas is a normal widget.
58 lines
1.4 KiB
Go
58 lines
1.4 KiB
Go
// Package sdl provides an SDL2 renderer for Doodle.
|
|
package sdl
|
|
|
|
import (
|
|
"git.kirsle.net/apps/doodle/render"
|
|
"github.com/veandco/go-sdl2/sdl"
|
|
)
|
|
|
|
// Clear the canvas and set this color.
|
|
func (r *Renderer) Clear(color render.Color) {
|
|
if color != r.lastColor {
|
|
r.renderer.SetDrawColor(color.Red, color.Green, color.Blue, color.Alpha)
|
|
}
|
|
r.renderer.Clear()
|
|
}
|
|
|
|
// DrawPoint puts a color at a pixel.
|
|
func (r *Renderer) DrawPoint(color render.Color, point render.Point) {
|
|
if color != r.lastColor {
|
|
r.renderer.SetDrawColor(color.Red, color.Green, color.Blue, color.Alpha)
|
|
}
|
|
r.renderer.DrawPoint(point.X, point.Y)
|
|
}
|
|
|
|
// DrawLine draws a line between two points.
|
|
func (r *Renderer) DrawLine(color render.Color, a, b render.Point) {
|
|
if color != r.lastColor {
|
|
r.renderer.SetDrawColor(color.Red, color.Green, color.Blue, color.Alpha)
|
|
}
|
|
r.renderer.DrawLine(a.X, a.Y, b.X, b.Y)
|
|
}
|
|
|
|
// DrawRect draws a rectangle.
|
|
func (r *Renderer) DrawRect(color render.Color, rect render.Rect) {
|
|
if color != r.lastColor {
|
|
r.renderer.SetDrawColor(color.Red, color.Green, color.Blue, color.Alpha)
|
|
}
|
|
r.renderer.DrawRect(&sdl.Rect{
|
|
X: rect.X,
|
|
Y: rect.Y,
|
|
W: rect.W,
|
|
H: rect.H,
|
|
})
|
|
}
|
|
|
|
// DrawBox draws a filled rectangle.
|
|
func (r *Renderer) DrawBox(color render.Color, rect render.Rect) {
|
|
if color != r.lastColor {
|
|
r.renderer.SetDrawColor(color.Red, color.Green, color.Blue, color.Alpha)
|
|
}
|
|
r.renderer.FillRect(&sdl.Rect{
|
|
X: rect.X,
|
|
Y: rect.Y,
|
|
W: rect.W,
|
|
H: rect.H,
|
|
})
|
|
}
|