GoRetro/component_sprite_renderer.go

package GoRetro

/*
 * --------------------
 * spriteRenderer
 * --------------------
 * Loads a BMP into a texture and stores dimensions
 */

import (
	"fmt"

	"github.com/veandco/go-sdl2/sdl"
)

type spriteRenderer struct {
	container     *Element
	tex           *sdl.Texture
	width, height int
}

func NewSpriteRenderer(container *Element, renderer *sdl.Renderer, filename string) *spriteRenderer {
	sr := &spriteRenderer{}
	var err error

	sr.tex, err = loadTextureFromBMP(filename, renderer)
	if err != nil {
		panic(err)
	}

	_, _, width, height, err := sr.tex.Query()
	if err != nil {
		panic(fmt.Errorf("querying texture: %v", err))
	}
	sr.width = int(width)
	sr.height = int(height)

	sr.container = container

	return sr
}

func (sr *spriteRenderer) onUpdate() error {
	return nil
}

func (sr *spriteRenderer) onDraw() error {
	Position := sr.container.Position
	if !sr.container.PositionAbsolute {
		Position = vectorAdd(sr.container.Position, ViewPort.Position)
	}

	return drawTexture(
		sr.tex,
		VectorInt32{-1, -1},
		VectorInt32{0, 0},
		Position,
		sr.container.Rotation,
		sr.container.Renderer)
}

func (sr *spriteRenderer) onCollision(other *Element) error {
	return nil
}