ebiten/internal/graphicsdriver/opengl/context_gl.go
2022-11-09 21:02:31 +09:00

515 lines
14 KiB
Go

// Copyright 2014 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.
//go:build !android && !ios && !js && !opengles
package opengl
import (
"errors"
"fmt"
"github.com/hajimehoshi/ebiten/v2/internal/graphicsdriver"
"github.com/hajimehoshi/ebiten/v2/internal/graphicsdriver/opengl/gl"
"github.com/hajimehoshi/ebiten/v2/internal/graphicsdriver/opengl/glconst"
"github.com/hajimehoshi/ebiten/v2/internal/shaderir"
)
type (
textureNative uint32
renderbufferNative uint32
framebufferNative uint32
shader uint32
program uint32
buffer uint32
)
func (t textureNative) equal(rhs textureNative) bool {
return t == rhs
}
func (r renderbufferNative) equal(rhs renderbufferNative) bool {
return r == rhs
}
func (f framebufferNative) equal(rhs framebufferNative) bool {
return f == rhs
}
func (s shader) equal(rhs shader) bool {
return s == rhs
}
func (b buffer) equal(rhs buffer) bool {
return b == rhs
}
func (u uniformLocation) equal(rhs uniformLocation) bool {
return u == rhs
}
func (p program) equal(rhs program) bool {
return p == rhs
}
var InvalidTexture textureNative
type (
uniformLocation int32
attribLocation int32
)
type programID uint32
const (
invalidTexture = 0
invalidFramebuffer = (1 << 32) - 1
invalidUniform = -1
)
func getProgramID(p program) programID {
return programID(p)
}
type contextImpl struct {
init bool
}
func (c *context) reset() error {
if !c.init {
// Note that this initialization must be done after Loop is called.
if err := gl.Init(); err != nil {
return fmt.Errorf("opengl: initializing error %v", err)
}
c.init = true
}
c.locationCache = newLocationCache()
c.lastTexture = invalidTexture
c.lastFramebuffer = invalidFramebuffer
c.lastViewportWidth = 0
c.lastViewportHeight = 0
c.lastBlend = graphicsdriver.Blend{}
gl.Enable(glconst.BLEND)
gl.Enable(glconst.SCISSOR_TEST)
// Set the source over blending.
c.blend(graphicsdriver.BlendSourceOver)
f := int32(0)
gl.GetIntegerv(glconst.FRAMEBUFFER_BINDING, &f)
c.screenFramebuffer = framebufferNative(f)
return nil
}
func (c *context) blend(blend graphicsdriver.Blend) {
if c.lastBlend == blend {
return
}
c.lastBlend = blend
gl.BlendFuncSeparate(
uint32(convertBlendFactor(blend.BlendFactorSourceRGB)),
uint32(convertBlendFactor(blend.BlendFactorDestinationRGB)),
uint32(convertBlendFactor(blend.BlendFactorSourceAlpha)),
uint32(convertBlendFactor(blend.BlendFactorDestinationAlpha)),
)
gl.BlendEquationSeparate(
uint32(convertBlendOperation(blend.BlendOperationRGB)),
uint32(convertBlendOperation(blend.BlendOperationAlpha)),
)
}
func (c *context) scissor(x, y, width, height int) {
gl.Scissor(int32(x), int32(y), int32(width), int32(height))
}
func (c *context) newTexture(width, height int) (textureNative, error) {
var t uint32
gl.GenTextures(1, &t)
// TODO: Use gl.IsTexture
if t <= 0 {
return 0, errors.New("opengl: creating texture failed")
}
texture := textureNative(t)
c.bindTexture(texture)
gl.TexParameteri(glconst.TEXTURE_2D, glconst.TEXTURE_MAG_FILTER, glconst.NEAREST)
gl.TexParameteri(glconst.TEXTURE_2D, glconst.TEXTURE_MIN_FILTER, glconst.NEAREST)
gl.TexParameteri(glconst.TEXTURE_2D, glconst.TEXTURE_WRAP_S, glconst.CLAMP_TO_EDGE)
gl.TexParameteri(glconst.TEXTURE_2D, glconst.TEXTURE_WRAP_T, glconst.CLAMP_TO_EDGE)
gl.PixelStorei(glconst.UNPACK_ALIGNMENT, 4)
// If data is nil, this just allocates memory and the content is undefined.
// https://www.khronos.org/registry/OpenGL-Refpages/gl4/html/glTexImage2D.xhtml
gl.TexImage2D(glconst.TEXTURE_2D, 0, glconst.RGBA, int32(width), int32(height), 0, glconst.RGBA, glconst.UNSIGNED_BYTE, nil)
return texture, nil
}
func (c *context) bindFramebufferImpl(f framebufferNative) {
gl.BindFramebufferEXT(glconst.FRAMEBUFFER, uint32(f))
}
func (c *context) framebufferPixels(buf []byte, f *framebuffer, x, y, width, height int) {
gl.Flush()
c.bindFramebuffer(f.native)
gl.ReadPixels(int32(x), int32(y), int32(width), int32(height), glconst.RGBA, glconst.UNSIGNED_BYTE, gl.Ptr(buf))
}
func (c *context) framebufferPixelsToBuffer(f *framebuffer, buffer buffer, width, height int) {
gl.Flush()
c.bindFramebuffer(f.native)
gl.BindBuffer(glconst.PIXEL_PACK_BUFFER, uint32(buffer))
gl.ReadPixels(0, 0, int32(width), int32(height), glconst.RGBA, glconst.UNSIGNED_BYTE, nil)
gl.BindBuffer(glconst.PIXEL_PACK_BUFFER, 0)
}
func (c *context) activeTexture(idx int) {
gl.ActiveTexture(glconst.TEXTURE0 + uint32(idx))
}
func (c *context) bindTextureImpl(t textureNative) {
gl.BindTexture(glconst.TEXTURE_2D, uint32(t))
}
func (c *context) deleteTexture(t textureNative) {
tt := uint32(t)
if !gl.IsTexture(tt) {
return
}
if c.lastTexture == t {
c.lastTexture = invalidTexture
}
gl.DeleteTextures(1, &tt)
}
func (c *context) isTexture(t textureNative) bool {
panic("opengl: isTexture is not implemented")
}
func (c *context) newRenderbuffer(width, height int) (renderbufferNative, error) {
var r uint32
gl.GenRenderbuffersEXT(1, &r)
if r <= 0 {
return 0, errors.New("opengl: creating renderbuffer failed")
}
renderbuffer := renderbufferNative(r)
c.bindRenderbuffer(renderbuffer)
// GL_STENCIL_INDEX8 might not be available with OpenGL 2.1.
// https://www.khronos.org/opengl/wiki/Image_Format
gl.RenderbufferStorageEXT(glconst.RENDERBUFFER, glconst.DEPTH24_STENCIL8, int32(width), int32(height))
return renderbuffer, nil
}
func (c *context) bindRenderbufferImpl(r renderbufferNative) {
gl.BindRenderbufferEXT(glconst.RENDERBUFFER, uint32(r))
}
func (c *context) deleteRenderbuffer(r renderbufferNative) {
rr := uint32(r)
if !gl.IsRenderbufferEXT(rr) {
return
}
if c.lastRenderbuffer.equal(r) {
c.lastRenderbuffer = 0
}
gl.DeleteRenderbuffersEXT(1, &rr)
}
func (c *context) newFramebuffer(texture textureNative) (framebufferNative, error) {
var f uint32
gl.GenFramebuffersEXT(1, &f)
if f <= 0 {
return 0, errors.New("opengl: creating framebuffer failed")
}
c.bindFramebuffer(framebufferNative(f))
gl.FramebufferTexture2DEXT(glconst.FRAMEBUFFER, glconst.COLOR_ATTACHMENT0, glconst.TEXTURE_2D, uint32(texture), 0)
s := gl.CheckFramebufferStatusEXT(glconst.FRAMEBUFFER)
if s != glconst.FRAMEBUFFER_COMPLETE {
if s != 0 {
return 0, fmt.Errorf("opengl: creating framebuffer failed: %v", s)
}
if e := gl.GetError(); e != glconst.NO_ERROR {
return 0, fmt.Errorf("opengl: creating framebuffer failed: (glGetError) %d", e)
}
return 0, fmt.Errorf("opengl: creating framebuffer failed: unknown error")
}
return framebufferNative(f), nil
}
func (c *context) bindStencilBuffer(f framebufferNative, r renderbufferNative) error {
c.bindFramebuffer(f)
gl.FramebufferRenderbufferEXT(glconst.FRAMEBUFFER, glconst.STENCIL_ATTACHMENT, glconst.RENDERBUFFER, uint32(r))
if s := gl.CheckFramebufferStatusEXT(glconst.FRAMEBUFFER); s != glconst.FRAMEBUFFER_COMPLETE {
return errors.New(fmt.Sprintf("opengl: glFramebufferRenderbuffer failed: %d", s))
}
return nil
}
func (c *context) setViewportImpl(width, height int) {
gl.Viewport(0, 0, int32(width), int32(height))
}
func (c *context) deleteFramebuffer(f framebufferNative) {
ff := uint32(f)
if !gl.IsFramebufferEXT(ff) {
return
}
if c.lastFramebuffer == f {
c.lastFramebuffer = invalidFramebuffer
c.lastViewportWidth = 0
c.lastViewportHeight = 0
}
gl.DeleteFramebuffersEXT(1, &ff)
}
func (c *context) newVertexShader(source string) (shader, error) {
return c.newShader(glconst.VERTEX_SHADER, source)
}
func (c *context) newFragmentShader(source string) (shader, error) {
return c.newShader(glconst.FRAGMENT_SHADER, source)
}
func (c *context) newShader(shaderType uint32, source string) (shader, error) {
s := gl.CreateShader(shaderType)
if s == 0 {
return 0, fmt.Errorf("opengl: glCreateShader failed: shader type: %d", shaderType)
}
cSources, free := gl.CStr(source)
gl.ShaderSource(uint32(s), 1, &cSources, nil)
free()
gl.CompileShader(s)
var v int32
gl.GetShaderiv(s, glconst.COMPILE_STATUS, &v)
if v == glconst.FALSE {
var l int32
var log []byte
gl.GetShaderiv(uint32(s), glconst.INFO_LOG_LENGTH, &l)
if l != 0 {
log = make([]byte, l)
gl.GetShaderInfoLog(s, l, nil, (*uint8)(gl.Ptr(log)))
}
return 0, fmt.Errorf("opengl: shader compile failed: %s", log)
}
return shader(s), nil
}
func (c *context) deleteShader(s shader) {
gl.DeleteShader(uint32(s))
}
func (c *context) newProgram(shaders []shader, attributes []string) (program, error) {
p := gl.CreateProgram()
if p == 0 {
return 0, errors.New("opengl: glCreateProgram failed")
}
for _, shader := range shaders {
gl.AttachShader(p, uint32(shader))
}
for i, name := range attributes {
l, free := gl.CStr(name)
gl.BindAttribLocation(p, uint32(i), l)
free()
}
gl.LinkProgram(p)
var v int32
gl.GetProgramiv(p, glconst.LINK_STATUS, &v)
if v == glconst.FALSE {
var l int32
var log []byte
gl.GetProgramiv(p, glconst.INFO_LOG_LENGTH, &l)
if l != 0 {
log = make([]byte, l)
gl.GetProgramInfoLog(p, l, nil, (*uint8)(gl.Ptr(log)))
}
return 0, fmt.Errorf("opengl: program error: %s", log)
}
return program(p), nil
}
func (c *context) useProgram(p program) {
gl.UseProgram(uint32(p))
}
func (c *context) deleteProgram(p program) {
c.locationCache.deleteProgram(p)
if !gl.IsProgram(uint32(p)) {
return
}
gl.DeleteProgram(uint32(p))
}
func (c *context) getUniformLocationImpl(p program, location string) uniformLocation {
l, free := gl.CStr(location)
uniform := uniformLocation(gl.GetUniformLocation(uint32(p), l))
free()
return uniform
}
func (c *context) uniformInt(p program, location string, v int) bool {
l := int32(c.locationCache.GetUniformLocation(c, p, location))
if l == invalidUniform {
return false
}
gl.Uniform1i(l, int32(v))
return true
}
func (c *context) uniformFloat(p program, location string, v float32) bool {
l := int32(c.locationCache.GetUniformLocation(c, p, location))
if l == invalidUniform {
return false
}
gl.Uniform1f(l, v)
return true
}
func (c *context) uniformFloats(p program, location string, v []float32, typ shaderir.Type) bool {
l := int32(c.locationCache.GetUniformLocation(c, p, location))
if l == invalidUniform {
return false
}
base := typ.Main
len := int32(1)
if base == shaderir.Array {
base = typ.Sub[0].Main
len = int32(typ.Length)
}
switch base {
case shaderir.Float:
gl.Uniform1fv(l, len, (*float32)(gl.Ptr(v)))
case shaderir.Vec2:
gl.Uniform2fv(l, len, (*float32)(gl.Ptr(v)))
case shaderir.Vec3:
gl.Uniform3fv(l, len, (*float32)(gl.Ptr(v)))
case shaderir.Vec4:
gl.Uniform4fv(l, len, (*float32)(gl.Ptr(v)))
case shaderir.Mat2:
gl.UniformMatrix2fv(l, len, false, (*float32)(gl.Ptr(v)))
case shaderir.Mat3:
gl.UniformMatrix3fv(l, len, false, (*float32)(gl.Ptr(v)))
case shaderir.Mat4:
gl.UniformMatrix4fv(l, len, false, (*float32)(gl.Ptr(v)))
default:
panic(fmt.Sprintf("opengl: unexpected type: %s", typ.String()))
}
return true
}
func (c *context) vertexAttribPointer(index int, size int, stride int, offset int) {
gl.VertexAttribPointer(uint32(index), int32(size), glconst.FLOAT, false, int32(stride), uintptr(offset))
}
func (c *context) enableVertexAttribArray(index int) {
gl.EnableVertexAttribArray(uint32(index))
}
func (c *context) disableVertexAttribArray(index int) {
gl.DisableVertexAttribArray(uint32(index))
}
func (c *context) newArrayBuffer(size int) buffer {
var b uint32
gl.GenBuffers(1, &b)
gl.BindBuffer(glconst.ARRAY_BUFFER, b)
gl.BufferData(glconst.ARRAY_BUFFER, size, nil, glconst.DYNAMIC_DRAW)
return buffer(b)
}
func (c *context) newElementArrayBuffer(size int) buffer {
var b uint32
gl.GenBuffers(1, &b)
gl.BindBuffer(glconst.ELEMENT_ARRAY_BUFFER, b)
gl.BufferData(glconst.ELEMENT_ARRAY_BUFFER, size, nil, glconst.DYNAMIC_DRAW)
return buffer(b)
}
func (c *context) bindArrayBuffer(b buffer) {
gl.BindBuffer(glconst.ARRAY_BUFFER, uint32(b))
}
func (c *context) bindElementArrayBuffer(b buffer) {
gl.BindBuffer(glconst.ELEMENT_ARRAY_BUFFER, uint32(b))
}
func (c *context) arrayBufferSubData(data []float32) {
gl.BufferSubData(glconst.ARRAY_BUFFER, 0, len(data)*4, gl.Ptr(data))
}
func (c *context) elementArrayBufferSubData(data []uint16) {
gl.BufferSubData(glconst.ELEMENT_ARRAY_BUFFER, 0, len(data)*2, gl.Ptr(data))
}
func (c *context) deleteBuffer(b buffer) {
bb := uint32(b)
gl.DeleteBuffers(1, &bb)
}
func (c *context) drawElements(len int, offsetInBytes int) {
gl.DrawElements(glconst.TRIANGLES, int32(len), glconst.UNSIGNED_SHORT, uintptr(offsetInBytes))
}
func (c *context) maxTextureSizeImpl() int {
s := int32(0)
gl.GetIntegerv(glconst.MAX_TEXTURE_SIZE, &s)
return int(s)
}
func (c *context) flush() {
gl.Flush()
}
func (c *context) needsRestoring() bool {
return false
}
func (c *context) texSubImage2D(t textureNative, args []*graphicsdriver.WritePixelsArgs) {
c.bindTexture(t)
for _, a := range args {
gl.TexSubImage2D(glconst.TEXTURE_2D, 0, int32(a.X), int32(a.Y), int32(a.Width), int32(a.Height), glconst.RGBA, glconst.UNSIGNED_BYTE, gl.Ptr(a.Pixels))
}
}
func (c *context) enableStencilTest() {
gl.Enable(glconst.STENCIL_TEST)
}
func (c *context) disableStencilTest() {
gl.Disable(glconst.STENCIL_TEST)
}
func (c *context) beginStencilWithEvenOddRule() {
gl.Clear(glconst.STENCIL_BUFFER_BIT)
gl.StencilFunc(glconst.ALWAYS, 0x00, 0xff)
gl.StencilOp(glconst.KEEP, glconst.KEEP, glconst.INVERT)
gl.ColorMask(false, false, false, false)
}
func (c *context) endStencilWithEvenOddRule() {
gl.StencilFunc(glconst.NOTEQUAL, 0x00, 0xff)
gl.StencilOp(glconst.KEEP, glconst.KEEP, glconst.KEEP)
gl.ColorMask(true, true, true, true)
}