From c9f445787e018b1c638a2ff797f3346914a43259 Mon Sep 17 00:00:00 2001
From: faiface <faiface@ksp.sk>
Date: Sat, 14 Jan 2017 16:07:51 +0100
Subject: [PATCH] add support for Picture slicing (Batch and Window)
---
batch.go | 22 +++++++++++++---------
util.go | 19 +++++++++++++++++++
window.go | 22 +++++++++++++++++++++-
3 files changed, 53 insertions(+), 10 deletions(-)
diff --git a/batch.go b/batch.go
index c69d617..b0d5e0a 100644
--- a/batch.go
+++ b/batch.go
@@ -12,7 +12,8 @@ import (
// To put an object into a Batch, just draw it onto it:
// object.Draw(batch)
type Batch struct {
- cont TrianglesDrawer
+ cont TrianglesDrawer
+ fixpic *Picture
pic *Picture
mat mgl32.Mat3
@@ -27,8 +28,8 @@ type Batch struct {
// Note, that if the container does not support TrianglesColor, color masking will not work.
func NewBatch(pic *Picture, container Triangles) *Batch {
return &Batch{
- cont: TrianglesDrawer{Triangles: container},
- pic: pic,
+ cont: TrianglesDrawer{Triangles: container},
+ fixpic: pic,
}
}
@@ -39,7 +40,7 @@ func (b *Batch) Clear() {
// Draw draws all objects that are currently in the Batch onto another Target.
func (b *Batch) Draw(t Target) {
- t.SetPicture(b.pic)
+ t.SetPicture(b.fixpic)
b.cont.Draw(t)
}
@@ -52,15 +53,16 @@ func (b *Batch) MakeTriangles(t Triangles) Triangles {
}
}
-// SetPicture only checks, whether the supplied Picture has the same underlying Picture as the fixed
-// Picture of this Batch. If that is not true, this method panics.
+// SetPicture sets the current Picture that will be used with the following draws. The underlying
+// Texture of this Picture must be same as the underlying Texture of the Batch's Picture.
func (b *Batch) SetPicture(p *Picture) {
if p == nil {
return
}
- if p.Texture() != b.pic.Texture() {
- panic("batch: attempted to draw with a different Picture")
+ if p.Texture() != b.fixpic.Texture() {
+ panic("batch: attempted to draw with a different underlying Picture")
}
+ b.pic = p
}
// SetTransform sets transforms used in the following draws onto the Batch.
@@ -96,7 +98,9 @@ func (bt *batchTriangles) Draw() {
})
bt.data[i].Position = V(float64(transPos.X()), float64(transPos.Y()))
bt.data[i].Color = bt.data[i].Color.Mul(bt.batch.col)
- //TODO: texture
+ if bt.batch.pic != nil && bt.data[i].Texture != V(-1, -1) {
+ bt.data[i].Texture = pictureBounds(bt.batch.pic, bt.data[i].Texture)
+ }
}
bt.trans.Update(&bt.data)
bt.batch.cont.Append(bt.trans)
diff --git a/util.go b/util.go
index ce46294..6aafdb8 100644
--- a/util.go
+++ b/util.go
@@ -12,6 +12,17 @@ func clamp(x, low, high float64) float64 {
return x
}
+func lerp(x float64, a, b Vec) Vec {
+ return a.Scaled(1-x) + b.Scaled(x)
+}
+
+func lerp2d(x, a, b Vec) Vec {
+ return V(
+ lerp(x.X(), a, b).X(),
+ lerp(x.Y(), a, b).Y(),
+ )
+}
+
func transformToMat(t ...Transform) mgl32.Mat3 {
mat := mgl32.Ident3()
for i := range t {
@@ -19,3 +30,11 @@ func transformToMat(t ...Transform) mgl32.Mat3 {
}
return mat
}
+
+func pictureBounds(p *Picture, v Vec) Vec {
+ w, h := float64(p.Texture().Width()), float64(p.Texture().Height())
+ a := p.Bounds().Pos
+ b := p.Bounds().Pos + p.Bounds().Size
+ u := lerp2d(v, a, b)
+ return V(u.X()/w, u.Y()/h)
+}
diff --git a/window.go b/window.go
index 8d70cd9..bc953b5 100644
--- a/window.go
+++ b/window.go
@@ -66,6 +66,7 @@ type Window struct {
pic *Picture
mat mgl32.Mat3
col mgl32.Vec4
+ bnd mgl32.Vec4
// need to save these to correctly restore a fullscreen window
restore struct {
@@ -374,12 +375,14 @@ func (wt *windowTriangles) Draw() {
pic := wt.w.pic // avoid
mat := wt.w.mat // race
col := wt.w.col // condition
+ bnd := wt.w.bnd
pixelgl.DoNoBlock(func() {
wt.w.begin()
wt.w.shader.SetUniformAttr(transformMat3, mat)
wt.w.shader.SetUniformAttr(maskColorVec4, col)
+ wt.w.shader.SetUniformAttr(boundsVec4, bnd)
if pic != nil {
pic.Texture().Begin()
@@ -514,6 +517,14 @@ func (w *Window) MakeTriangles(t Triangles) Triangles {
// SetPicture sets a Picture that will be used in subsequent drawings onto the window.
func (w *Window) SetPicture(p *Picture) {
+ if p != nil {
+ min := pictureBounds(p, V(0, 0))
+ max := pictureBounds(p, V(1, 1))
+ w.bnd = mgl32.Vec4{
+ float32(min.X()), float32(min.Y()),
+ float32(max.X()), float32(max.Y()),
+ }
+ }
w.pic = p
}
@@ -552,11 +563,13 @@ var defaultVertexFormat = pixelgl.AttrFormat{
const (
maskColorVec4 int = iota
transformMat3
+ boundsVec4
)
var defaultUniformFormat = pixelgl.AttrFormat{
{Name: "maskColor", Type: pixelgl.Vec4},
{Name: "transform", Type: pixelgl.Mat3},
+ {Name: "bounds", Type: pixelgl.Vec4},
}
var defaultVertexShader = `
@@ -587,13 +600,20 @@ in vec2 Texture;
out vec4 color;
uniform vec4 maskColor;
+uniform vec4 bounds;
uniform sampler2D tex;
void main() {
+ vec2 boundsMin = bounds.xy;
+ vec2 boundsMax = bounds.zw;
+
+ float tx = boundsMin.x * (1 - Texture.x) + boundsMax.x * Texture.x;
+ float ty = boundsMin.y * (1 - Texture.y) + boundsMax.y * Texture.y;
+
if (Texture == vec2(-1, -1)) {
color = maskColor * Color;
} else {
- color = maskColor * Color * texture(tex, vec2(Texture.x, 1 - Texture.y));
+ color = maskColor * Color * texture(tex, vec2(tx, 1 - ty));
}
}
`
--
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