50 lines
664 B
Go
50 lines
664 B
Go
package gx
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import (
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"math"
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)
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// Implements the camera component
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// for the main window.
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type Camera struct {
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T Transform
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}
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const (
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Pi = math.Pi
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)
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// Returns the matrix satysfying camera
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// position, scale and rotation to apply
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// it to the objects to get the real
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// transform to display on the screen.
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// (Should implement buffering it so we do not
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// need to calculate it each time for each object. )
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func (c *Camera)RealMatrix(
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e *Engine,
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scale bool,
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) Matrix {
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g := &Matrix{}
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if scale {
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g.Scale(
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c.T.S.X,
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c.T.S.Y,
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)
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}
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g.Translate(
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-c.T.P.X,
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c.T.P.Y,
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)
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g.Rotate(-c.T.R)
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g.Translate(
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c.T.RA.X,
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-c.T.RA.Y,
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)
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return *g
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}
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