mirror of
				https://github.com/hajimehoshi/ebiten.git
				synced 2025-10-31 03:36:21 +08:00 
			
		
		
		
	
		
			
				
	
	
		
			119 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			119 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
| // Copyright 2016 Hajime Hoshi
 | |
| //
 | |
| // Licensed under the Apache License, Version 2.0 (the "License");
 | |
| // you may not use this file except in compliance with the License.
 | |
| // You may obtain a copy of the License at
 | |
| //
 | |
| //     http://www.apache.org/licenses/LICENSE-2.0
 | |
| //
 | |
| // Unless required by applicable law or agreed to in writing, software
 | |
| // distributed under the License is distributed on an "AS IS" BASIS,
 | |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 | |
| // See the License for the specific language governing permissions and
 | |
| // limitations under the License.
 | |
| 
 | |
| package opengl
 | |
| 
 | |
| import (
 | |
| 	"fmt"
 | |
| 	"sync"
 | |
| 
 | |
| 	"github.com/hajimehoshi/ebiten/internal/driver"
 | |
| 	"github.com/hajimehoshi/ebiten/internal/thread"
 | |
| )
 | |
| 
 | |
| func convertOperation(op driver.Operation) operation {
 | |
| 	switch op {
 | |
| 	case driver.Zero:
 | |
| 		return zero
 | |
| 	case driver.One:
 | |
| 		return one
 | |
| 	case driver.SrcAlpha:
 | |
| 		return srcAlpha
 | |
| 	case driver.DstAlpha:
 | |
| 		return dstAlpha
 | |
| 	case driver.OneMinusSrcAlpha:
 | |
| 		return oneMinusSrcAlpha
 | |
| 	case driver.OneMinusDstAlpha:
 | |
| 		return oneMinusDstAlpha
 | |
| 	default:
 | |
| 		panic(fmt.Sprintf("opengl: invalid operation %d at convertOperation", op))
 | |
| 	}
 | |
| }
 | |
| 
 | |
| type context struct {
 | |
| 	locationCache      *locationCache
 | |
| 	screenFramebuffer  framebufferNative // This might not be the default frame buffer '0' (e.g. iOS).
 | |
| 	lastFramebuffer    framebufferNative
 | |
| 	lastTexture        textureNative
 | |
| 	lastViewportWidth  int
 | |
| 	lastViewportHeight int
 | |
| 	lastCompositeMode  driver.CompositeMode
 | |
| 	maxTextureSize     int
 | |
| 	maxTextureSizeOnce sync.Once
 | |
| 	highp              bool
 | |
| 	highpOnce          sync.Once
 | |
| 
 | |
| 	t *thread.Thread
 | |
| 
 | |
| 	contextImpl
 | |
| }
 | |
| 
 | |
| func (c *context) bindTexture(t textureNative) {
 | |
| 	if c.lastTexture.equal(t) {
 | |
| 		return
 | |
| 	}
 | |
| 	c.bindTextureImpl(t)
 | |
| 	c.lastTexture = t
 | |
| }
 | |
| 
 | |
| func (c *context) bindFramebuffer(f framebufferNative) {
 | |
| 	if c.lastFramebuffer.equal(f) {
 | |
| 		return
 | |
| 	}
 | |
| 	c.bindFramebufferImpl(f)
 | |
| 	c.lastFramebuffer = f
 | |
| }
 | |
| 
 | |
| func (c *context) setViewport(f *framebuffer) {
 | |
| 	c.bindFramebuffer(f.native)
 | |
| 	if c.lastViewportWidth != f.width || c.lastViewportHeight != f.height {
 | |
| 		// On some environments, viewport size must be within the framebuffer size.
 | |
| 		// e.g. Edge (#71), Chrome on GPD Pocket (#420), macOS Mojave (#691).
 | |
| 		// Use the same size of the framebuffer here.
 | |
| 		c.setViewportImpl(f.width, f.height)
 | |
| 
 | |
| 		// glViewport must be called at least at every frame on iOS.
 | |
| 		// As the screen framebuffer is the last render target, next SetViewport should be
 | |
| 		// the first call at a frame.
 | |
| 		if f.native.equal(c.screenFramebuffer) {
 | |
| 			c.lastViewportWidth = 0
 | |
| 			c.lastViewportHeight = 0
 | |
| 		} else {
 | |
| 			c.lastViewportWidth = f.width
 | |
| 			c.lastViewportHeight = f.height
 | |
| 		}
 | |
| 	}
 | |
| }
 | |
| 
 | |
| func (c *context) getScreenFramebuffer() framebufferNative {
 | |
| 	return c.screenFramebuffer
 | |
| }
 | |
| 
 | |
| func (c *context) getMaxTextureSize() int {
 | |
| 	c.maxTextureSizeOnce.Do(func() {
 | |
| 		c.maxTextureSize = c.maxTextureSizeImpl()
 | |
| 	})
 | |
| 	return c.maxTextureSize
 | |
| }
 | |
| 
 | |
| // highpPrecision represents an enough mantissa of float values in a shader.
 | |
| const highpPrecision = 23
 | |
| 
 | |
| func (c *context) hasHighPrecisionFloat() bool {
 | |
| 	c.highpOnce.Do(func() {
 | |
| 		c.highp = c.getShaderPrecisionFormatPrecision() >= highpPrecision
 | |
| 	})
 | |
| 	return c.highp
 | |
| }
 | 
