diff options
-rw-r--r-- | src/library_browser.js | 9 | ||||
-rw-r--r-- | src/library_gl.js | 193 |
2 files changed, 138 insertions, 64 deletions
diff --git a/src/library_browser.js b/src/library_browser.js index d5e35339..458a8dd2 100644 --- a/src/library_browser.js +++ b/src/library_browser.js @@ -775,6 +775,15 @@ mergeInto(LibraryManager.library, { return; } + // Signal GL rendering layer that processing of a new frame is about to start. This helps it optimize + // VBO double-buffering and reduce GPU stalls. +#if FULL_ES2 + GL.newRenderingFrameStarted(); +#endif +#if LEGACY_GL_EMULATION + GL.newRenderingFrameStarted(); +#endif + if (Module['preMainLoop']) { Module['preMainLoop'](); } diff --git a/src/library_gl.js b/src/library_gl.js index f6978c04..899638e8 100644 --- a/src/library_gl.js +++ b/src/library_gl.js @@ -57,6 +57,7 @@ var LibraryGL = { unpackAlignment: 4, // default alignment is 4 bytes init: function() { + GL.createLog2ceilLookup(GL.MAX_TEMP_BUFFER_SIZE); Browser.moduleContextCreatedCallbacks.push(GL.initExtensions); }, @@ -81,36 +82,58 @@ var LibraryGL = { miniTempBuffer: null, miniTempBufferViews: [0], // index i has the view of size i+1 - // Large temporary buffers + // When user GL code wants to render from client-side memory, we need to upload the vertex data to a temp VBO + // for rendering. Maintain a set of temp VBOs that are created-on-demand to appropriate sizes, and never destroyed. + // Also, for best performance the VBOs are double-buffered, i.e. every second frame we switch the set of VBOs we + // upload to, so that rendering from the previous frame is not disturbed by uploading from new data to it, which + // could cause a GPU-CPU pipeline stall. + // Note that index buffers are not double-buffered (at the moment) in this manner. MAX_TEMP_BUFFER_SIZE: {{{ GL_MAX_TEMP_BUFFER_SIZE }}}, - tempBufferIndexLookup: null, - tempVertexBuffers: null, - tempIndexBuffers: null, + tempVertexBuffers1: [], + tempVertexBufferCounters1: [], + tempVertexBuffers2: [], + tempVertexBufferCounters2: [], + // Maximum number of temp VBOs of one size to maintain, after that we start reusing old ones, which is safe but can give + // a performance impact. If CPU-GPU stalls are a problem, increasing this might help. + numTempVertexBuffersPerSize: 64, // (const) + tempIndexBuffers: [], tempQuadIndexBuffer: null, - generateTempBuffers: function(quads) { - GL.tempBufferIndexLookup = new Uint8Array(GL.MAX_TEMP_BUFFER_SIZE+1); - GL.tempVertexBuffers = []; - GL.tempIndexBuffers = []; - var last = -1, curr = -1; - var size = 1; - for (var i = 0; i <= GL.MAX_TEMP_BUFFER_SIZE; i++) { - if (i > size) { - size <<= 1; + // Precompute a lookup table for the function ceil(log2(x)), i.e. how many bits are needed to represent x, or, + // if x was rounded up to next pow2, which index is the single '1' bit at? + // Then log2ceilLookup[x] returns ceil(log2(x)). + log2ceilLookup: null, + createLog2ceilLookup: function(maxValue) { + GL.log2ceilLookup = new Uint8Array(maxValue+1); + var log2 = 0; + var pow2 = 1; + GL.log2ceilLookup[0] = 0; + for(var i = 1; i <= maxValue; ++i) { + if (i > pow2) { + pow2 <<= 1; + ++log2; } - if (size != last) { - curr++; - GL.tempVertexBuffers[curr] = GLctx.createBuffer(); - GLctx.bindBuffer(GLctx.ARRAY_BUFFER, GL.tempVertexBuffers[curr]); - GLctx.bufferData(GLctx.ARRAY_BUFFER, size, GLctx.DYNAMIC_DRAW); - GLctx.bindBuffer(GLctx.ARRAY_BUFFER, null); - GL.tempIndexBuffers[curr] = GLctx.createBuffer(); - GLctx.bindBuffer(GLctx.ELEMENT_ARRAY_BUFFER, GL.tempIndexBuffers[curr]); - GLctx.bufferData(GLctx.ELEMENT_ARRAY_BUFFER, size, GLctx.DYNAMIC_DRAW); - GLctx.bindBuffer(GLctx.ELEMENT_ARRAY_BUFFER, null); - last = size; + GL.log2ceilLookup[i] = log2; + } + }, + + generateTempBuffers: function(quads) { + var largestIndex = GL.log2ceilLookup[GL.MAX_TEMP_BUFFER_SIZE]; + GL.tempVertexBufferCounters1.length = GL.tempVertexBufferCounters2.length = largestIndex+1; + GL.tempVertexBuffers1.length = GL.tempVertexBuffers2.length = largestIndex+1; + GL.tempIndexBuffers.length = largestIndex+1; + for(var i = 0; i <= largestIndex; ++i) { + GL.tempIndexBuffers[i] = null; // Created on-demand + GL.tempVertexBufferCounters1[i] = GL.tempVertexBufferCounters2[i] = 0; + var ringbufferLength = GL.numTempVertexBuffersPerSize; + GL.tempVertexBuffers1[i] = []; + GL.tempVertexBuffers2[i] = []; + var ringbuffer1 = GL.tempVertexBuffers1[i]; + var ringbuffer2 = GL.tempVertexBuffers2[i]; + ringbuffer1.length = ringbuffer2.length = ringbufferLength; + for(var j = 0; j < ringbufferLength; ++j) { + ringbuffer1[j] = ringbuffer2[j] = null; // Created on-demand } - GL.tempBufferIndexLookup[i] = curr; } if (quads) { @@ -140,6 +163,53 @@ var LibraryGL = { } }, + getTempVertexBuffer: function getTempVertexBuffer(sizeBytes) { + var idx = GL.log2ceilLookup[sizeBytes]; + var ringbuffer = GL.tempVertexBuffers1[idx]; + var nextFreeBufferIndex = GL.tempVertexBufferCounters1[idx]; + GL.tempVertexBufferCounters1[idx] = (GL.tempVertexBufferCounters1[idx]+1) & (GL.numTempVertexBuffersPerSize-1); + var vbo = ringbuffer[nextFreeBufferIndex]; + if (vbo) { + return vbo; + } + var prevVBO = GLctx.getParameter(GLctx.ARRAY_BUFFER_BINDING); + ringbuffer[nextFreeBufferIndex] = GLctx.createBuffer(); + GLctx.bindBuffer(GLctx.ARRAY_BUFFER, ringbuffer[nextFreeBufferIndex]); + GLctx.bufferData(GLctx.ARRAY_BUFFER, 1 << idx, GLctx.DYNAMIC_DRAW); + GLctx.bindBuffer(GLctx.ARRAY_BUFFER, prevVBO); + return ringbuffer[nextFreeBufferIndex]; + }, + + getTempIndexBuffer: function getTempIndexBuffer(sizeBytes) { + var idx = GL.log2ceilLookup[sizeBytes]; + var ibo = GL.tempIndexBuffers[idx]; + if (ibo) { + return ibo; + } + var prevIBO = GLctx.getParameter(GLctx.ELEMENT_ARRAY_BUFFER_BINDING); + GL.tempIndexBuffers[idx] = GLctx.createBuffer(); + GLctx.bindBuffer(GLctx.ELEMENT_ARRAY_BUFFER, GL.tempIndexBuffers[idx]); + GLctx.bufferData(GLctx.ELEMENT_ARRAY_BUFFER, 1 << idx, GLctx.DYNAMIC_DRAW); + GLctx.bindBuffer(GLctx.ELEMENT_ARRAY_BUFFER, prevIBO); + return GL.tempIndexBuffers[idx]; + }, + + // Called at start of each new WebGL rendering frame. This swaps the doublebuffered temp VB memory pointers, + // so that every second frame utilizes different set of temp buffers. The aim is to keep the set of buffers + // being rendered, and the set of buffers being updated disjoint. + newRenderingFrameStarted: function newRenderingFrameStarted() { + var vb = GL.tempVertexBuffers1; + GL.tempVertexBuffers1 = GL.tempVertexBuffers2; + GL.tempVertexBuffers2 = vb; + vb = GL.tempVertexBufferCounters1; + GL.tempVertexBufferCounters1 = GL.tempVertexBufferCounters2; + GL.tempVertexBufferCounters2 = vb; + var largestIndex = GL.log2ceilLookup[GL.MAX_TEMP_BUFFER_SIZE]; + for(var i = 0; i <= largestIndex; ++i) { + GL.tempVertexBufferCounters1[i] = 0; + } + }, + // Find a token in a shader source string findToken: function(source, token) { function isIdentChar(ch) { @@ -446,9 +516,6 @@ var LibraryGL = { preDrawHandleClientVertexAttribBindings: function preDrawHandleClientVertexAttribBindings(count) { GL.resetBufferBinding = false; - var used = GL.usedTempBuffers; - used.length = 0; - // TODO: initial pass to detect ranges we need to upload, might not need an upload per attrib for (var i = 0; i < GL.maxVertexAttribs; ++i) { var cb = GL.clientBuffers[i]; @@ -457,15 +524,7 @@ var LibraryGL = { GL.resetBufferBinding = true; var size = GL.calcBufLength(cb.size, cb.type, cb.stride, count); - var index = GL.tempBufferIndexLookup[size]; - var buf; - do { -#if ASSERTIONS - assert(index < GL.tempVertexBuffers.length); -#endif - buf = GL.tempVertexBuffers[index++]; - } while (used.indexOf(buf) >= 0); - used.push(buf); + var buf = GL.getTempVertexBuffer(size); GLctx.bindBuffer(GLctx.ARRAY_BUFFER, buf); GLctx.bufferSubData(GLctx.ARRAY_BUFFER, 0, @@ -2742,14 +2801,6 @@ var LibraryGL = { this.key0 = -1; // The key of this texture unit must be recomputed when rendering the next time. GLImmediate.currentRenderer = null; // The currently used renderer must be re-evaluated at next render. } - this.traverseState = function(keyView) { - if (this.key0 == -1) { - this.recomputeKey(); - } - keyView.next(this.key0); - keyView.next(this.key1); - keyView.next(this.key2); - }; } function CTexUnit() { @@ -2758,18 +2809,26 @@ var LibraryGL = { this.enabled_tex2D = false; this.enabled_tex3D = false; this.enabled_texCube = false; + this.texTypesEnabled = 0; // A bitfield combination of the four flags above, used for fast access to operations. this.traverseState = function CTexUnit_traverseState(keyView) { - var texUnitType = this.getTexType(); - keyView.next(texUnitType); - if (!texUnitType) return; - this.env.traverseState(keyView); + if (this.texTypesEnabled) { + if (this.env.key0 == -1) { + this.env.recomputeKey(); + } + keyView.next(this.texTypesEnabled | (this.env.key0 << 4)); + keyView.next(this.env.key1); + keyView.next(this.env.key2); + } else { + // For correctness, must traverse a zero value, theoretically a subsequent integer key could collide with this value otherwise. + keyView.next(0); + } }; }; // Class impls: CTexUnit.prototype.enabled = function CTexUnit_enabled() { - return this.getTexType() != 0; + return this.texTypesEnabled; } CTexUnit.prototype.genPassLines = function CTexUnit_genPassLines(passOutputVar, passInputVar, texUnitID) { @@ -3084,12 +3143,7 @@ var LibraryGL = { traverseState: function(keyView) { for (var i = 0; i < s_texUnits.length; i++) { - var texUnit = s_texUnits[i]; - var enabled = texUnit.enabled(); - keyView.next(enabled); - if (enabled) { - texUnit.traverseState(keyView); - } + s_texUnits[i].traverseState(keyView); } }, @@ -3113,24 +3167,28 @@ var LibraryGL = { if (!cur.enabled_tex1D) { GLImmediate.currentRenderer = null; // Renderer state changed, and must be recreated or looked up again. cur.enabled_tex1D = true; + cur.texTypesEnabled |= 1; } break; case GL_TEXTURE_2D: if (!cur.enabled_tex2D) { GLImmediate.currentRenderer = null; cur.enabled_tex2D = true; + cur.texTypesEnabled |= 2; } break; case GL_TEXTURE_3D: if (!cur.enabled_tex3D) { GLImmediate.currentRenderer = null; cur.enabled_tex3D = true; + cur.texTypesEnabled |= 4; } break; case GL_TEXTURE_CUBE_MAP: if (!cur.enabled_texCube) { GLImmediate.currentRenderer = null; cur.enabled_texCube = true; + cur.texTypesEnabled |= 8; } break; } @@ -3143,24 +3201,28 @@ var LibraryGL = { if (cur.enabled_tex1D) { GLImmediate.currentRenderer = null; // Renderer state changed, and must be recreated or looked up again. cur.enabled_tex1D = false; + cur.texTypesEnabled &= ~1; } break; case GL_TEXTURE_2D: if (cur.enabled_tex2D) { GLImmediate.currentRenderer = null; cur.enabled_tex2D = false; + cur.texTypesEnabled &= ~2; } break; case GL_TEXTURE_3D: if (cur.enabled_tex3D) { GLImmediate.currentRenderer = null; cur.enabled_tex3D = false; + cur.texTypesEnabled &= ~4; } break; case GL_TEXTURE_CUBE_MAP: if (cur.enabled_texCube) { GLImmediate.currentRenderer = null; cur.enabled_texCube = false; + cur.texTypesEnabled &= ~8; } break; } @@ -3434,7 +3496,6 @@ var LibraryGL = { // we maintain a cache of renderers, optimized to not generate garbage var attributes = GLImmediate.liveClientAttributes; var cacheMap = GLImmediate.rendererCache; - var temp; var keyView = cacheMap.getStaticKeyView().reset(); // By attrib state: @@ -3442,7 +3503,6 @@ var LibraryGL = { for (var i = 0; i < attributes.length; i++) { enabledAttributesKey |= 1 << attributes[i].name; } - keyView.next(enabledAttributesKey); // By fog state: var fogParam = 0; @@ -3459,13 +3519,17 @@ var LibraryGL = { break; } } - keyView.next(fogParam); + keyView.next((enabledAttributesKey << 2) | fogParam); +#if !GL_FFP_ONLY // By cur program: keyView.next(GL.currProgram); if (!GL.currProgram) { +#endif GLImmediate.TexEnvJIT.traverseState(keyView); +#if !GL_FFP_ONLY } +#endif // If we don't already have it, create it. var renderer = keyView.get(); @@ -3720,7 +3784,7 @@ var LibraryGL = { #if ASSERTIONS assert(end <= GL.MAX_TEMP_BUFFER_SIZE, 'too much vertex data'); #endif - arrayBuffer = GL.tempVertexBuffers[GL.tempBufferIndexLookup[end]]; + arrayBuffer = GL.getTempVertexBuffer(end); // TODO: consider using the last buffer we bound, if it was larger. downside is larger buffer, but we might avoid rebinding and preparing } else { arrayBuffer = GL.currArrayBuffer; @@ -4028,11 +4092,12 @@ var LibraryGL = { if (!Module.useWebGL) return; // a 2D canvas may be currently used TODO: make sure we are actually called in that case - GLImmediate.TexEnvJIT.init(GLctx); - // User can override the maximum number of texture units that we emulate. Using fewer texture units increases runtime performance // slightly, so it is advantageous to choose as small value as needed. GLImmediate.MAX_TEXTURES = Module['GL_MAX_TEXTURE_IMAGE_UNITS'] || GLctx.getParameter(GLctx.MAX_TEXTURE_IMAGE_UNITS); + + GLImmediate.TexEnvJIT.init(GLctx, GLImmediate.MAX_TEXTURES); + GLImmediate.NUM_ATTRIBUTES = 3 /*pos+normal+color attributes*/ + GLImmediate.MAX_TEXTURES; GLImmediate.clientAttributes = []; GLEmulation.enabledClientAttribIndices = []; @@ -4221,7 +4286,7 @@ var LibraryGL = { #if ASSERTIONS assert(numProvidedIndexes << 1 <= GL.MAX_TEMP_BUFFER_SIZE, 'too many immediate mode indexes (a)'); #endif - var indexBuffer = GL.tempIndexBuffers[GL.tempBufferIndexLookup[numProvidedIndexes << 1]]; + var indexBuffer = GL.getTempIndexBuffer(numProvidedIndexes << 1); GLctx.bindBuffer(GLctx.ELEMENT_ARRAY_BUFFER, indexBuffer); GLctx.bufferSubData(GLctx.ELEMENT_ARRAY_BUFFER, 0, {{{ makeHEAPView('U16', 'ptr', 'ptr + (numProvidedIndexes << 1)') }}}); ptr = 0; @@ -4986,7 +5051,7 @@ var LibraryGL = { var buf; if (!GL.currElementArrayBuffer) { var size = GL.calcBufLength(1, type, 0, count); - buf = GL.tempIndexBuffers[GL.tempBufferIndexLookup[size]]; + buf = GL.getTempIndexBuffer(size); GLctx.bindBuffer(GLctx.ELEMENT_ARRAY_BUFFER, buf); GLctx.bufferSubData(GLctx.ELEMENT_ARRAY_BUFFER, 0, |