ebiten/internal/opengl/context.go
2018-11-07 01:43:07 +09:00

116 lines
2.9 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 (
"github.com/hajimehoshi/ebiten/internal/graphics"
)
var (
vertexShader shaderType
fragmentShader shaderType
arrayBuffer bufferType
elementArrayBuffer bufferType
dynamicDraw bufferUsage
staticDraw bufferUsage
short dataType
float dataType
zero operation
one operation
srcAlpha operation
dstAlpha operation
oneMinusSrcAlpha operation
oneMinusDstAlpha operation
)
func convertOperation(op graphics.Operation) operation {
switch op {
case graphics.Zero:
return zero
case graphics.One:
return one
case graphics.SrcAlpha:
return srcAlpha
case graphics.DstAlpha:
return dstAlpha
case graphics.OneMinusSrcAlpha:
return oneMinusSrcAlpha
case graphics.OneMinusDstAlpha:
return oneMinusDstAlpha
default:
panic("not reached")
}
}
// TODO: Unexport this
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 graphics.CompositeMode
maxTextureSize int
context
}
var theContext Context
func (c *Context) bindTexture(t textureNative) {
if c.lastTexture == t {
return
}
c.bindTextureImpl(t)
c.lastTexture = t
}
func (c *Context) bindFramebuffer(f framebufferNative) {
if c.lastFramebuffer == 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 {
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 == 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 {
if c.maxTextureSize == 0 {
c.maxTextureSize = c.maxTextureSizeImpl()
}
return c.maxTextureSize
}