three
Version:
JavaScript 3D library
414 lines (233 loc) • 8.56 kB
JavaScript
function WebGLUniformsGroups( gl, info, capabilities, state ) {
let buffers = {};
let updateList = {};
let allocatedBindingPoints = [];
const maxBindingPoints = ( capabilities.isWebGL2 ) ? gl.getParameter( gl.MAX_UNIFORM_BUFFER_BINDINGS ) : 0; // binding points are global whereas block indices are per shader program
function bind( uniformsGroup, program ) {
const webglProgram = program.program;
state.uniformBlockBinding( uniformsGroup, webglProgram );
}
function update( uniformsGroup, program ) {
let buffer = buffers[ uniformsGroup.id ];
if ( buffer === undefined ) {
prepareUniformsGroup( uniformsGroup );
buffer = createBuffer( uniformsGroup );
buffers[ uniformsGroup.id ] = buffer;
uniformsGroup.addEventListener( 'dispose', onUniformsGroupsDispose );
}
// ensure to update the binding points/block indices mapping for this program
const webglProgram = program.program;
state.updateUBOMapping( uniformsGroup, webglProgram );
// update UBO once per frame
const frame = info.render.frame;
if ( updateList[ uniformsGroup.id ] !== frame ) {
updateBufferData( uniformsGroup );
updateList[ uniformsGroup.id ] = frame;
}
}
function createBuffer( uniformsGroup ) {
// the setup of an UBO is independent of a particular shader program but global
const bindingPointIndex = allocateBindingPointIndex();
uniformsGroup.__bindingPointIndex = bindingPointIndex;
const buffer = gl.createBuffer();
const size = uniformsGroup.__size;
const usage = uniformsGroup.usage;
gl.bindBuffer( gl.UNIFORM_BUFFER, buffer );
gl.bufferData( gl.UNIFORM_BUFFER, size, usage );
gl.bindBuffer( gl.UNIFORM_BUFFER, null );
gl.bindBufferBase( gl.UNIFORM_BUFFER, bindingPointIndex, buffer );
return buffer;
}
function allocateBindingPointIndex() {
for ( let i = 0; i < maxBindingPoints; i ++ ) {
if ( allocatedBindingPoints.indexOf( i ) === - 1 ) {
allocatedBindingPoints.push( i );
return i;
}
}
console.error( 'THREE.WebGLRenderer: Maximum number of simultaneously usable uniforms groups reached.' );
return 0;
}
function updateBufferData( uniformsGroup ) {
const buffer = buffers[ uniformsGroup.id ];
const uniforms = uniformsGroup.uniforms;
const cache = uniformsGroup.__cache;
gl.bindBuffer( gl.UNIFORM_BUFFER, buffer );
for ( let i = 0, il = uniforms.length; i < il; i ++ ) {
const uniform = uniforms[ i ];
// partly update the buffer if necessary
if ( hasUniformChanged( uniform, i, cache ) === true ) {
const offset = uniform.__offset;
const values = Array.isArray( uniform.value ) ? uniform.value : [ uniform.value ];
let arrayOffset = 0;
for ( let i = 0; i < values.length; i ++ ) {
const value = values[ i ];
const info = getUniformSize( value );
if ( typeof value === 'number' ) {
uniform.__data[ 0 ] = value;
gl.bufferSubData( gl.UNIFORM_BUFFER, offset + arrayOffset, uniform.__data );
} else if ( value.isMatrix3 ) {
// manually converting 3x3 to 3x4
uniform.__data[ 0 ] = value.elements[ 0 ];
uniform.__data[ 1 ] = value.elements[ 1 ];
uniform.__data[ 2 ] = value.elements[ 2 ];
uniform.__data[ 3 ] = value.elements[ 0 ];
uniform.__data[ 4 ] = value.elements[ 3 ];
uniform.__data[ 5 ] = value.elements[ 4 ];
uniform.__data[ 6 ] = value.elements[ 5 ];
uniform.__data[ 7 ] = value.elements[ 0 ];
uniform.__data[ 8 ] = value.elements[ 6 ];
uniform.__data[ 9 ] = value.elements[ 7 ];
uniform.__data[ 10 ] = value.elements[ 8 ];
uniform.__data[ 11 ] = value.elements[ 0 ];
} else {
value.toArray( uniform.__data, arrayOffset );
arrayOffset += info.storage / Float32Array.BYTES_PER_ELEMENT;
}
}
gl.bufferSubData( gl.UNIFORM_BUFFER, offset, uniform.__data );
}
}
gl.bindBuffer( gl.UNIFORM_BUFFER, null );
}
function hasUniformChanged( uniform, index, cache ) {
const value = uniform.value;
if ( cache[ index ] === undefined ) {
// cache entry does not exist so far
if ( typeof value === 'number' ) {
cache[ index ] = value;
} else {
const values = Array.isArray( value ) ? value : [ value ];
const tempValues = [];
for ( let i = 0; i < values.length; i ++ ) {
tempValues.push( values[ i ].clone() );
}
cache[ index ] = tempValues;
}
return true;
} else {
// compare current value with cached entry
if ( typeof value === 'number' ) {
if ( cache[ index ] !== value ) {
cache[ index ] = value;
return true;
}
} else {
const cachedObjects = Array.isArray( cache[ index ] ) ? cache[ index ] : [ cache[ index ] ];
const values = Array.isArray( value ) ? value : [ value ];
for ( let i = 0; i < cachedObjects.length; i ++ ) {
const cachedObject = cachedObjects[ i ];
if ( cachedObject.equals( values[ i ] ) === false ) {
cachedObject.copy( values[ i ] );
return true;
}
}
}
}
return false;
}
function prepareUniformsGroup( uniformsGroup ) {
// determine total buffer size according to the STD140 layout
// Hint: STD140 is the only supported layout in WebGL 2
const uniforms = uniformsGroup.uniforms;
let offset = 0; // global buffer offset in bytes
const chunkSize = 16; // size of a chunk in bytes
let chunkOffset = 0; // offset within a single chunk in bytes
for ( let i = 0, l = uniforms.length; i < l; i ++ ) {
const uniform = uniforms[ i ];
const infos = {
boundary: 0, // bytes
storage: 0 // bytes
};
const values = Array.isArray( uniform.value ) ? uniform.value : [ uniform.value ];
for ( let j = 0, jl = values.length; j < jl; j ++ ) {
const value = values[ j ];
const info = getUniformSize( value );
infos.boundary += info.boundary;
infos.storage += info.storage;
}
// the following two properties will be used for partial buffer updates
uniform.__data = new Float32Array( infos.storage / Float32Array.BYTES_PER_ELEMENT );
uniform.__offset = offset;
//
if ( i > 0 ) {
chunkOffset = offset % chunkSize;
const remainingSizeInChunk = chunkSize - chunkOffset;
// check for chunk overflow
if ( chunkOffset !== 0 && ( remainingSizeInChunk - infos.boundary ) < 0 ) {
// add padding and adjust offset
offset += ( chunkSize - chunkOffset );
uniform.__offset = offset;
}
}
offset += infos.storage;
}
// ensure correct final padding
chunkOffset = offset % chunkSize;
if ( chunkOffset > 0 ) offset += ( chunkSize - chunkOffset );
//
uniformsGroup.__size = offset;
uniformsGroup.__cache = {};
return this;
}
function getUniformSize( value ) {
const info = {
boundary: 0, // bytes
storage: 0 // bytes
};
// determine sizes according to STD140
if ( typeof value === 'number' ) {
// float/int
info.boundary = 4;
info.storage = 4;
} else if ( value.isVector2 ) {
// vec2
info.boundary = 8;
info.storage = 8;
} else if ( value.isVector3 || value.isColor ) {
// vec3
info.boundary = 16;
info.storage = 12; // evil: vec3 must start on a 16-byte boundary but it only consumes 12 bytes
} else if ( value.isVector4 ) {
// vec4
info.boundary = 16;
info.storage = 16;
} else if ( value.isMatrix3 ) {
// mat3 (in STD140 a 3x3 matrix is represented as 3x4)
info.boundary = 48;
info.storage = 48;
} else if ( value.isMatrix4 ) {
// mat4
info.boundary = 64;
info.storage = 64;
} else if ( value.isTexture ) {
console.warn( 'THREE.WebGLRenderer: Texture samplers can not be part of an uniforms group.' );
} else {
console.warn( 'THREE.WebGLRenderer: Unsupported uniform value type.', value );
}
return info;
}
function onUniformsGroupsDispose( event ) {
const uniformsGroup = event.target;
uniformsGroup.removeEventListener( 'dispose', onUniformsGroupsDispose );
const index = allocatedBindingPoints.indexOf( uniformsGroup.__bindingPointIndex );
allocatedBindingPoints.splice( index, 1 );
gl.deleteBuffer( buffers[ uniformsGroup.id ] );
delete buffers[ uniformsGroup.id ];
delete updateList[ uniformsGroup.id ];
}
function dispose() {
for ( const id in buffers ) {
gl.deleteBuffer( buffers[ id ] );
}
allocatedBindingPoints = [];
buffers = {};
updateList = {};
}
return {
bind: bind,
update: update,
dispose: dispose
};
}
export { WebGLUniformsGroups };