mirror of
https://github.com/hajimehoshi/ebiten.git
synced 2024-11-10 13:07:26 +01:00
306 lines
8.7 KiB
Go
306 lines
8.7 KiB
Go
package opengl
|
|
|
|
// #cgo LDFLAGS: -framework OpenGL
|
|
//
|
|
// #include <stdlib.h>
|
|
// #include <OpenGL/gl.h>
|
|
import "C"
|
|
import (
|
|
"fmt"
|
|
"github.com/hajimehoshi/go.ebiten/graphics"
|
|
"github.com/hajimehoshi/go.ebiten/graphics/matrix"
|
|
"image"
|
|
"image/color"
|
|
"unsafe"
|
|
)
|
|
|
|
type GraphicsContext struct {
|
|
screenWidth int
|
|
screenHeight int
|
|
screenScale int
|
|
textures map[graphics.TextureID]*Texture
|
|
projectionMatrix [16]float32
|
|
currentShaderProgram C.GLuint
|
|
mainFramebuffer C.GLuint
|
|
framebuffers map[C.GLuint]C.GLuint
|
|
}
|
|
|
|
// This method should be called on the UI thread.
|
|
func newGraphicsContext(screenWidth, screenHeight, screenScale int) *GraphicsContext {
|
|
context := &GraphicsContext{
|
|
screenWidth: screenWidth,
|
|
screenHeight: screenHeight,
|
|
screenScale: screenScale,
|
|
textures: map[graphics.TextureID]*Texture{},
|
|
mainFramebuffer: 0,
|
|
framebuffers: map[C.GLuint]C.GLuint{},
|
|
}
|
|
// main framebuffer should be created sooner than any other framebuffers!
|
|
mainFramebuffer := C.GLint(0)
|
|
C.glGetIntegerv(C.GL_FRAMEBUFFER_BINDING, &mainFramebuffer)
|
|
context.mainFramebuffer = C.GLuint(mainFramebuffer)
|
|
|
|
initializeShaders()
|
|
|
|
return context
|
|
}
|
|
|
|
func (context *GraphicsContext) Clear() {
|
|
C.glClearColor(0, 0, 0, 1)
|
|
C.glClear(C.GL_COLOR_BUFFER_BIT)
|
|
}
|
|
|
|
func (context *GraphicsContext) Fill(clr color.Color) {
|
|
r, g, b, a := clr.RGBA()
|
|
max := 65535.0
|
|
C.glClearColor(
|
|
C.GLclampf(float64(r)/max),
|
|
C.GLclampf(float64(g)/max),
|
|
C.GLclampf(float64(b)/max),
|
|
C.GLclampf(float64(a)/max))
|
|
C.glClear(C.GL_COLOR_BUFFER_BIT)
|
|
}
|
|
|
|
func (context *GraphicsContext) DrawRect(x, y, width, height int, clr color.Color) {
|
|
// TODO: implement!
|
|
}
|
|
|
|
func (context *GraphicsContext) DrawTexture(
|
|
texture graphics.Texture,
|
|
geometryMatrix matrix.Geometry, colorMatrix matrix.Color) {
|
|
source := graphics.Rect{0, 0, texture.Width, texture.Height}
|
|
locations := []graphics.TextureLocation{{0, 0, source}}
|
|
context.DrawTextureParts(texture.ID, locations,
|
|
geometryMatrix, colorMatrix)
|
|
}
|
|
|
|
func (context *GraphicsContext) DrawTextureParts(
|
|
textureID graphics.TextureID, locations []graphics.TextureLocation,
|
|
geometryMatrix matrix.Geometry, colorMatrix matrix.Color) {
|
|
|
|
texture := context.textures[textureID]
|
|
|
|
context.setShaderProgram(geometryMatrix, colorMatrix)
|
|
C.glBindTexture(C.GL_TEXTURE_2D, texture.id)
|
|
|
|
vertexAttrLocation := getAttributeLocation(context.currentShaderProgram, "vertex")
|
|
textureAttrLocation := getAttributeLocation(context.currentShaderProgram, "texture")
|
|
|
|
C.glEnableClientState(C.GL_VERTEX_ARRAY)
|
|
C.glEnableClientState(C.GL_TEXTURE_COORD_ARRAY)
|
|
C.glEnableVertexAttribArray(C.GLuint(vertexAttrLocation))
|
|
C.glEnableVertexAttribArray(C.GLuint(textureAttrLocation))
|
|
for _, location := range locations {
|
|
x1 := float32(location.LocationX)
|
|
x2 := float32(location.LocationX + location.Source.Width)
|
|
y1 := float32(location.LocationY)
|
|
y2 := float32(location.LocationY + location.Source.Height)
|
|
vertex := [...]float32{
|
|
x1, y1,
|
|
x2, y1,
|
|
x1, y2,
|
|
x2, y2,
|
|
}
|
|
|
|
src := location.Source
|
|
tu1 := float32(src.X) / float32(texture.textureWidth)
|
|
tu2 := float32(src.X+src.Width) / float32(texture.textureWidth)
|
|
tv1 := float32(src.Y) / float32(texture.textureHeight)
|
|
tv2 := float32(src.Y+src.Height) / float32(texture.textureHeight)
|
|
texCoord := [...]float32{
|
|
tu1, tv1,
|
|
tu2, tv1,
|
|
tu1, tv2,
|
|
tu2, tv2,
|
|
}
|
|
C.glVertexAttribPointer(C.GLuint(vertexAttrLocation), 2, C.GL_FLOAT, C.GL_FALSE,
|
|
0, unsafe.Pointer(&vertex[0]))
|
|
C.glVertexAttribPointer(C.GLuint(textureAttrLocation), 2, C.GL_FLOAT, C.GL_FALSE,
|
|
0, unsafe.Pointer(&texCoord[0]))
|
|
C.glDrawArrays(C.GL_TRIANGLE_STRIP, 0, 4)
|
|
}
|
|
C.glDisableVertexAttribArray(C.GLuint(textureAttrLocation))
|
|
C.glDisableVertexAttribArray(C.GLuint(vertexAttrLocation))
|
|
C.glDisableClientState(C.GL_TEXTURE_COORD_ARRAY)
|
|
C.glDisableClientState(C.GL_VERTEX_ARRAY)
|
|
}
|
|
|
|
func abs(x int) int {
|
|
if x < 0 {
|
|
return -x
|
|
}
|
|
return x
|
|
}
|
|
|
|
func (context *GraphicsContext) SetOffscreen(textureID graphics.TextureID) {
|
|
texture := context.textures[textureID]
|
|
framebuffer := context.getFramebuffer(texture.id)
|
|
if framebuffer == context.mainFramebuffer {
|
|
panic("invalid framebuffer")
|
|
}
|
|
context.setOffscreenFramebuffer(framebuffer,
|
|
texture.textureWidth, texture.textureHeight)
|
|
}
|
|
|
|
func (context *GraphicsContext) setOffscreenFramebuffer(framebuffer C.GLuint,
|
|
textureWidth, textureHeight int) {
|
|
C.glFlush()
|
|
|
|
C.glBindFramebuffer(C.GL_FRAMEBUFFER, framebuffer)
|
|
if err := C.glCheckFramebufferStatus(C.GL_FRAMEBUFFER); err != C.GL_FRAMEBUFFER_COMPLETE {
|
|
panic(fmt.Sprintf("glBindFramebuffer failed: %d", err))
|
|
}
|
|
C.glEnable(C.GL_BLEND)
|
|
C.glBlendFunc(C.GL_SRC_ALPHA, C.GL_ONE_MINUS_SRC_ALPHA)
|
|
|
|
width, height, tx, ty := 0, 0, 0, 0
|
|
if framebuffer != context.mainFramebuffer {
|
|
width = textureWidth
|
|
height = textureHeight
|
|
tx = -1
|
|
ty = -1
|
|
} else {
|
|
width = context.screenWidth * context.screenScale
|
|
height = -1 * context.screenHeight * context.screenScale
|
|
tx = -1
|
|
ty = 1
|
|
}
|
|
C.glViewport(0, 0, C.GLsizei(abs(width)), C.GLsizei(abs(height)))
|
|
e11 := float32(2.0) / float32(width)
|
|
e22 := float32(2.0) / float32(height)
|
|
e41 := float32(tx)
|
|
e42 := float32(ty)
|
|
context.projectionMatrix = [...]float32{
|
|
e11, 0, 0, 0,
|
|
0, e22, 0, 0,
|
|
0, 0, 1, 0,
|
|
e41, e42, 0, 1,
|
|
}
|
|
}
|
|
|
|
func (context *GraphicsContext) resetOffscreen() {
|
|
context.setOffscreenFramebuffer(context.mainFramebuffer, 0, 0)
|
|
}
|
|
|
|
// This method should be called on the UI thread.
|
|
func (context *GraphicsContext) flush() {
|
|
C.glFlush()
|
|
}
|
|
|
|
// This method should be called on the UI thread.
|
|
func (context *GraphicsContext) setShaderProgram(
|
|
geometryMatrix matrix.Geometry, colorMatrix matrix.Color) {
|
|
program := C.GLuint(0)
|
|
if colorMatrix.IsIdentity() {
|
|
program = regularShaderProgram
|
|
} else {
|
|
program = colorMatrixShaderProgram
|
|
}
|
|
// TODO: cache and skip?
|
|
C.glUseProgram(program)
|
|
context.currentShaderProgram = program
|
|
|
|
C.glUniformMatrix4fv(getUniformLocation(program, "projection_matrix"),
|
|
1, C.GL_FALSE,
|
|
(*C.GLfloat)(&context.projectionMatrix[0]))
|
|
|
|
a := float32(geometryMatrix.Elements[0][0])
|
|
b := float32(geometryMatrix.Elements[0][1])
|
|
c := float32(geometryMatrix.Elements[1][0])
|
|
d := float32(geometryMatrix.Elements[1][1])
|
|
tx := float32(geometryMatrix.Elements[0][2])
|
|
ty := float32(geometryMatrix.Elements[1][2])
|
|
glModelviewMatrix := [...]float32{
|
|
a, c, 0, 0,
|
|
b, d, 0, 0,
|
|
0, 0, 1, 0,
|
|
tx, ty, 0, 1,
|
|
}
|
|
C.glUniformMatrix4fv(getUniformLocation(program, "modelview_matrix"),
|
|
1, C.GL_FALSE,
|
|
(*C.GLfloat)(&glModelviewMatrix[0]))
|
|
|
|
C.glUniform1i(getUniformLocation(program, "texture"), 0)
|
|
|
|
if program != colorMatrixShaderProgram {
|
|
return
|
|
}
|
|
|
|
e := [4][5]float32{}
|
|
for i := 0; i < 4; i++ {
|
|
for j := 0; j < 5; j++ {
|
|
e[i][j] = float32(colorMatrix.Elements[i][j])
|
|
}
|
|
}
|
|
|
|
glColorMatrix := [...]float32{
|
|
e[0][0], e[0][1], e[0][2], e[0][3],
|
|
e[1][0], e[1][1], e[1][2], e[1][3],
|
|
e[2][0], e[2][1], e[2][2], e[2][3],
|
|
e[3][0], e[3][1], e[3][2], e[3][3],
|
|
}
|
|
C.glUniformMatrix4fv(getUniformLocation(program, "color_matrix"),
|
|
1, C.GL_FALSE, (*C.GLfloat)(&glColorMatrix[0]))
|
|
|
|
glColorMatrixTranslation := [...]float32{
|
|
e[0][4], e[1][4], e[2][4], e[3][4],
|
|
}
|
|
C.glUniform4fv(getUniformLocation(program, "color_matrix_translation"),
|
|
1, (*C.GLfloat)(&glColorMatrixTranslation[0]))
|
|
}
|
|
|
|
func (context *GraphicsContext) getFramebuffer(textureID C.GLuint) C.GLuint {
|
|
framebuffer, ok := context.framebuffers[textureID]
|
|
if ok {
|
|
return framebuffer
|
|
}
|
|
|
|
newFramebuffer := C.GLuint(0)
|
|
C.glGenFramebuffers(1, &newFramebuffer)
|
|
|
|
origFramebuffer := C.GLint(0)
|
|
C.glGetIntegerv(C.GL_FRAMEBUFFER_BINDING, &origFramebuffer)
|
|
C.glBindFramebuffer(C.GL_FRAMEBUFFER, newFramebuffer)
|
|
C.glFramebufferTexture2D(C.GL_FRAMEBUFFER, C.GL_COLOR_ATTACHMENT0,
|
|
C.GL_TEXTURE_2D, textureID, 0)
|
|
C.glBindFramebuffer(C.GL_FRAMEBUFFER, C.GLuint(origFramebuffer))
|
|
if C.glCheckFramebufferStatus(C.GL_FRAMEBUFFER) != C.GL_FRAMEBUFFER_COMPLETE {
|
|
panic("creating framebuffer failed")
|
|
}
|
|
|
|
context.framebuffers[textureID] = newFramebuffer
|
|
return newFramebuffer
|
|
}
|
|
|
|
func (context *GraphicsContext) deleteFramebuffer(textureID C.GLuint) {
|
|
framebuffer, ok := context.framebuffers[textureID]
|
|
if !ok {
|
|
// TODO: panic?
|
|
return
|
|
}
|
|
C.glDeleteFramebuffers(1, &framebuffer)
|
|
delete(context.framebuffers, textureID)
|
|
}
|
|
|
|
func (context *GraphicsContext) NewTexture(width, height int) graphics.Texture {
|
|
texture := newTexture(width, height)
|
|
id := graphics.TextureID(texture.id)
|
|
context.textures[id] = texture
|
|
return graphics.Texture{
|
|
ID: id,
|
|
Width: texture.width,
|
|
Height: texture.height,
|
|
}
|
|
}
|
|
|
|
func (context *GraphicsContext) NewTextureFromImage(img image.Image) graphics.Texture {
|
|
texture := newTextureFromImage(img)
|
|
id := graphics.TextureID(texture.id)
|
|
context.textures[id] = texture
|
|
return graphics.Texture{
|
|
ID: id,
|
|
Width: texture.width,
|
|
Height: texture.height,
|
|
}
|
|
}
|