internal/graphicsdriver/opengl: refactoring

internal/graphicsdriver/opengl/context.go

@@ -124,7 +124,6 @@ type context struct {
 	maxTextureSizeOnce sync.Once
 	highp              bool
 	highpOnce          sync.Once
-	initOnce           sync.Once
 
 	contextPlatform
 }
@@ -191,25 +190,14 @@ func (c *context) getMaxTextureSize() int {
 	return c.maxTextureSize
 }
 
-func (c *context) reset() error {
-	var err1 error
-	c.initOnce.Do(func() {
-		// Load OpenGL functions after WGL is initialized especially for Windows (#2452).
-		if err := c.ctx.LoadFunctions(); err != nil {
-			err1 = err
-			return
-		}
-	})
-	if err1 != nil {
-		return err1
+func (c *context) init() error {
+	// Load OpenGL functions after WGL is initialized especially for Windows (#2452).
+	if err := c.ctx.LoadFunctions(); err != nil {
+		return err
 	}
 
 	c.locationCache = newLocationCache()
-	c.lastTexture = 0
 	c.lastFramebuffer = invalidFramebuffer
-	c.lastViewportWidth = 0
-	c.lastViewportHeight = 0
-	c.lastBlend = graphicsdriver.Blend{}
 
 	c.ctx.Enable(gl.BLEND)
 	c.ctx.Enable(gl.SCISSOR_TEST)

internal/graphicsdriver/opengl/graphics.go

@@ -146,12 +146,7 @@ func (g *Graphics) removeImage(img *Image) {
 }
 
 func (g *Graphics) Initialize() error {
-	return g.state.reset(&g.context)
-}
-
-// Reset resets or initializes the current OpenGL state.
-func (g *Graphics) Reset() error {
-	return g.state.reset(&g.context)
+	return g.context.init()
 }
 
 func (g *Graphics) SetVertices(vertices []float32, indices []uint16) error {

internal/graphicsdriver/opengl/program.go

@@ -16,7 +16,6 @@ package opengl
 
 import (
 	"fmt"
-	"runtime"
 	"unsafe"
 
 	"github.com/hajimehoshi/ebiten/v2/internal/graphics"
@@ -122,34 +121,6 @@ type openGLState struct {
 	lastActiveTexture int
 }
 
-// reset resets or initializes the OpenGL state.
-func (s *openGLState) reset(context *context) error {
-	if err := context.reset(); err != nil {
-		return err
-	}
-
-	s.lastProgram = 0
-	context.ctx.UseProgram(0)
-	for key := range s.lastUniforms {
-		delete(s.lastUniforms, key)
-	}
-
-	// On browsers (at least Chrome), buffers are already detached from the context
-	// and must not be deleted by DeleteBuffer.
-	if runtime.GOOS != "js" {
-		if s.arrayBuffer != 0 {
-			context.ctx.DeleteBuffer(uint32(s.arrayBuffer))
-		}
-		if s.elementArrayBuffer != 0 {
-			context.ctx.DeleteBuffer(uint32(s.elementArrayBuffer))
-		}
-	}
-	s.arrayBuffer = 0
-	s.elementArrayBuffer = 0
-
-	return nil
-}
-
 func (s *openGLState) setVertices(context *context, vertices []float32, indices []uint16) {
 	if s.arrayBuffer == 0 {
 		s.arrayBuffer = context.newArrayBuffer(graphics.IndicesCount * graphics.VertexFloatCount * floatSizeInBytes)