updated light.go added basic lighting example

examples/shaders/mesh_instancing/light.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"fmt"
-	"reflect"
 	"unsafe"
 
 	rl "github.com/gen2brain/raylib-go/raylib"
@@ -22,7 +21,6 @@ type Light struct {
 	target    rl.Vector3
 	color     rl.Color
 	enabled   int32
-
 	// shader locations
 	enabledLoc int32
 	typeLoc    int32
@@ -40,46 +38,32 @@ func NewLight(
 	position, target rl.Vector3,
 	color rl.Color,
 	shader rl.Shader) Light {
-
 	light := Light{
 		shader: shader,
 	}
-
 	if lightCount < maxLightsCount {
 		light.enabled = 1
 		light.lightType = lightType
 		light.position = position
 		light.target = target
 		light.color = color
-
 		light.enabledLoc = rl.GetShaderLocation(shader, fmt.Sprintf("lights[%d].enabled", lightCount))
 		light.typeLoc = rl.GetShaderLocation(shader, fmt.Sprintf("lights[%d].type", lightCount))
 		light.posLoc = rl.GetShaderLocation(shader, fmt.Sprintf("lights[%d].position", lightCount))
 		light.targetLoc = rl.GetShaderLocation(shader, fmt.Sprintf("lights[%d].target", lightCount))
 		light.colorLoc = rl.GetShaderLocation(shader, fmt.Sprintf("lights[%d].color", lightCount))
 		light.UpdateValues()
-
 		lightCount++
 	}
-
 	return light
 }
 
-// Send light properties to shader
 func (lt *Light) UpdateValues() {
-	// not pretty -_-
-	// need nicer api
-	sh := &reflect.SliceHeader{
-		Len: 4,
-		Cap: 4,
-	}
-
 	// Send to shader light enabled state and type
-	sh.Data = uintptr(unsafe.Pointer(&lt.enabled))
-	rl.SetShaderValue(lt.shader, lt.enabledLoc, *(*[]float32)(unsafe.Pointer(sh)), rl.ShaderUniformInt)
+	rl.SetShaderValue(lt.shader, lt.enabledLoc, unsafe.Slice((*float32)(unsafe.Pointer(&lt.enabled)), 4), rl.ShaderUniformInt)
+	rl.SetShaderValue(lt.shader, lt.typeLoc, unsafe.Slice((*float32)(unsafe.Pointer(&lt.lightType)), 4), rl.ShaderUniformInt)
 
 	// Send to shader light position values
-	sh.Data = uintptr(unsafe.Pointer(&lt.lightType))
 	rl.SetShaderValue(lt.shader, lt.posLoc, []float32{lt.position.X, lt.position.Y, lt.position.Z}, rl.ShaderUniformVec3)
 
 	// Send to shader light target target values