diff --git a/Sec3Engine/demos/ParticleDemo.js b/Sec3Engine/demos/ParticleDemo.js
index 2b57493..11e99ca 100644
--- a/Sec3Engine/demos/ParticleDemo.js
+++ b/Sec3Engine/demos/ParticleDemo.js
@@ -279,10 +279,11 @@ function startDemo() {
SEC3ENGINE.run(gl);
}
-function webGLStart() {
+ function webGLStart() {
- canvas = document.getElementById("glcanvas");
- initGL(canvas);
+ canvas = document.getElementById("glcanvas");
+ SEC3.canvas = canvas;
+ initGL(canvas);
camera = SEC3ENGINE.createCamera(CAMERA_TRACKING_TYPE);
camera.goHome([0.0, 0.0, 10.0]);
diff --git a/Sec3Engine/demos/SEC3DEMO.js b/Sec3Engine/demos/SEC3DEMO.js
index 0c489ca..ae70a9f 100644
--- a/Sec3Engine/demos/SEC3DEMO.js
+++ b/Sec3Engine/demos/SEC3DEMO.js
@@ -513,6 +513,19 @@ var setupScene = function(canvasId, messageId ) {
console.log("Bad GL Context!");
return;
}
+
+ // The renderer relies on multiple render targets, which require the
+ // WEBGL_draw_buffers extension in WebGL 1. Prefer to fail fast when the
+ // extension is unavailable (for example, when the browser has reduced GPU
+ // support enabled) rather than letting the pipeline fail later with vague
+ // WebGL errors.
+ if (!gl.getExtension("WEBGL_draw_buffers")) {
+ console.warn("WEBGL_draw_buffers extension unavailable; rendering will fail.");
+ if (msg) {
+ msg.innerText = "WEBGL_draw_buffers is required for SEC3DEMO.";
+ }
+ return;
+ }
gl.viewport( 0, 0, canvas.width, canvas.height );
gl.viewportWidth = canvas.width;
diff --git a/Sec3Engine/js/core/ParticleSystem.js b/Sec3Engine/js/core/ParticleSystem.js
index e15338d..752609a 100644
--- a/Sec3Engine/js/core/ParticleSystem.js
+++ b/Sec3Engine/js/core/ParticleSystem.js
@@ -43,18 +43,39 @@ SEC3.createParticleSystem = function(specs) {
var renderProgram;
var stepProgram;
- var interactor = {};
- interactor.attractor = [ -13.0, 6.0, 1.0, 1.0 ];
- var self = {};
+ var interactor = {};
+ interactor.attractor = [ -13.0, 6.0, 1.0, 1.0 ];
+ var self = {};
+
+ // Helpers to safely access optional scene and camera globals used by legacy demos.
+ var getActiveCamera = function() {
+ if (typeof scene !== "undefined" && scene.getCamera) {
+ return scene.getCamera();
+ }
+ if (typeof camera !== "undefined") {
+ return camera;
+ }
+ return null;
+ };
+
+ var getActiveLight = function() {
+ if (typeof scene !== "undefined" && scene.getLight && scene.getNumLights && scene.getNumLights() > 0) {
+ return scene.getLight(0);
+ }
+ return null;
+ };
//----------------------------------------------------------------METHODS:
- var update = function() {
+ var update = function() {
- stepParticles();
- updateShadowMap(scene.getLight(0));
- };
+ stepParticles();
+ var activeLight = getActiveLight();
+ if (activeLight) {
+ updateShadowMap(activeLight);
+ }
+ };
var draw = function( light ) {
renderParticles( light );
@@ -96,11 +117,14 @@ SEC3.createParticleSystem = function(specs) {
gl.vertexAttribPointer(stepProgram.aVertexPosition, 2, gl.FLOAT, false, 0, 0);
gl.enableVertexAttribArray(stepProgram.aVertexPosition);
- var center = vec3.clone(scene.getCamera().getPosition());
- var offset = vec3.clone(camera.normal);
- vec3.scale(offset, offset, -6.0);
- vec3.add(center, center, offset);
- gl.uniform4f(stepProgram.uAttractor, center[0], center[1], center[2], 0.4 );
+ var activeCamera = getActiveCamera();
+ if (activeCamera) {
+ var center = vec3.clone(activeCamera.getPosition());
+ var offset = vec3.clone(activeCamera.normal);
+ vec3.scale(offset, offset, -6.0);
+ vec3.add(center, center, offset);
+ gl.uniform4f(stepProgram.uAttractor, center[0], center[1], center[2], 0.4 );
+ }
gl.drawArrays(gl.TRIANGLES, 0, 6);
}
@@ -108,9 +132,13 @@ SEC3.createParticleSystem = function(specs) {
/*
* draws current scene into shadow map
*/
- var updateShadowMap = function ( light ) {
+ var updateShadowMap = function ( light ) {
+
+ if (!light || !light.cascadeFramebuffers || !light.cascadeFramebuffers[0]) {
+ return;
+ }
- var fbo = light.cascadeFramebuffers[0];
+ var fbo = light.cascadeFramebuffers[0];
gl.colorMask(false,false,false,false);
gl.useProgram(self.shadowProgram.ref());
gl.viewport(0, 0, fbo.getWidth(), fbo.getHeight());
@@ -139,30 +167,49 @@ SEC3.createParticleSystem = function(specs) {
/*
* Draws all particles in system
*/
- var renderParticles = function ( light ) {
+ var renderParticles = function ( light ) {
+
+ light = light || getActiveLight();
+ if (!light || !light.cascadeFramebuffers || !light.cascadeFramebuffers[0]) {
+ return;
+ }
gl.useProgram(self.renderProgram.ref());
gl.viewport(0, 0, SEC3.canvas.width, SEC3.canvas.height );
- gl.uniform3fv(renderProgram.uLightPosition, light.getPosition());
- gl.uniform3fv(renderProgram.uCPosLoc, scene.getCamera().getPosition());
-
- gl.activeTexture(gl.TEXTURE0);
- gl.bindTexture(gl.TEXTURE_2D, positionTextures[srcIndex]);
- gl.uniform1i( renderProgram.uParticlePositions, 0);
-
- gl.activeTexture( gl.TEXTURE1 );
- gl.bindTexture( gl.TEXTURE_2D, SEC3.gBuffer.depthTexture() );
- gl.uniform1i( renderProgram.uGDepthLoc, 1 );
-
- gl.activeTexture(gl.TEXTURE2);
- gl.bindTexture(gl.TEXTURE_2D, light.cascadeFramebuffers[0].depthTexture() );
- gl.uniform1i(renderProgram.uShadowMap, 2);
-
- gl.uniformMatrix4fv(renderProgram.uShadowMapTransform, false, light.getMVP() );
- gl.uniformMatrix4fv(renderProgram.uCameraTransform, false, scene.getCamera().getMVP());
- gl.uniform3fv(renderProgram.uLightPosition, light.getPosition() );
+ if (light) {
+ gl.uniform3fv(renderProgram.uLightPosition, light.getPosition());
+ }
+ var activeCamera = getActiveCamera();
+ if (activeCamera) {
+ gl.uniform3fv(renderProgram.uCPosLoc, activeCamera.getPosition());
+ }
+
+ gl.activeTexture(gl.TEXTURE0);
+ gl.bindTexture(gl.TEXTURE_2D, positionTextures[srcIndex]);
+ gl.uniform1i( renderProgram.uParticlePositions, 0);
+
+ if (SEC3.gBuffer && SEC3.gBuffer.depthTexture) {
+ gl.activeTexture( gl.TEXTURE1 );
+ gl.bindTexture( gl.TEXTURE_2D, SEC3.gBuffer.depthTexture() );
+ gl.uniform1i( renderProgram.uGDepthLoc, 1 );
+ }
+
+ if (light) {
+ gl.activeTexture(gl.TEXTURE2);
+ gl.bindTexture(gl.TEXTURE_2D, light.cascadeFramebuffers[0].depthTexture() );
+ gl.uniform1i(renderProgram.uShadowMap, 2);
+
+ gl.uniformMatrix4fv(renderProgram.uShadowMapTransform, false, light.getMVP() );
+ }
+ var activeCamera = getActiveCamera();
+ if (activeCamera) {
+ gl.uniformMatrix4fv(renderProgram.uCameraTransform, false, activeCamera.getMVP());
+ }
+ if (light) {
+ gl.uniform3fv(renderProgram.uLightPosition, light.getPosition() );
+ }
//bind the default frame buffer, disable depth testing and enable alpha blending
finalFBO.bind(gl);
@@ -293,8 +340,14 @@ SEC3.createParticleSystem = function(specs) {
renderProgram.uShadowMultiply = gl.getUniformLocation(renderProgram.ref(), "uShadowMultiply");
renderProgram.uScale = gl.getUniformLocation(renderProgram.ref(), "uScale");
gl.useProgram(renderProgram.ref());
- gl.uniformMatrix4fv(renderProgram.uShadowMapTransform, false, scene.getLight(0).getMVP());
- gl.uniformMatrix4fv(renderProgram.uCameraTransform, false, scene.getCamera().getMVP());
+ var activeLight = getActiveLight();
+ if (activeLight) {
+ gl.uniformMatrix4fv(renderProgram.uShadowMapTransform, false, activeLight.getMVP());
+ }
+ var activeCamera = getActiveCamera();
+ if (activeCamera) {
+ gl.uniformMatrix4fv(renderProgram.uCameraTransform, false, activeCamera.getMVP());
+ }
gl.uniform2fv( renderProgram.uScreenSizeLoc, vec2.fromValues(SEC3.canvas.width, SEC3.canvas.height ));
gl.uniform1f(renderProgram.uLuminence, self.luminence);
gl.uniform1f(renderProgram.uAlpha, self.RGBA[3]);
diff --git a/Sec3Engine/js/core/camera.js b/Sec3Engine/js/core/camera.js
index e2050c1..5576b73 100644
--- a/Sec3Engine/js/core/camera.js
+++ b/Sec3Engine/js/core/camera.js
@@ -6,10 +6,20 @@
//SEC3 is a core function interface
var SEC3 = SEC3 || {};
+// Camera type constants expected by legacy demos.
+var CAMERA_EXPLORING_TYPE = 0;
+var CAMERA_TRACKING_TYPE = 1;
+
SEC3.Camera = function(){
-
+
SEC3.PerspProjector.call( this );
};
-
-SEC3.Camera.prototype = Object.create( SEC3.PerspProjector.prototype );
\ No newline at end of file
+
+SEC3.Camera.prototype = Object.create( SEC3.PerspProjector.prototype );
+
+// Convenience factory used by demo pages.
+SEC3.createCamera = function(/* type */){
+ // Only one camera type is implemented; ignore the requested type for now.
+ return new SEC3.Camera();
+};
diff --git a/Sec3Engine/js/core/shader-util.js b/Sec3Engine/js/core/shader-util.js
index 06c0877..93d8a27 100644
--- a/Sec3Engine/js/core/shader-util.js
+++ b/Sec3Engine/js/core/shader-util.js
@@ -16,10 +16,22 @@ SEC3.createShaderProgram = function(){
var program = null; //shader program
var callbackFunArray = [];
- function loadShaderFile( gl, fileName, shader, prefix ){
+ function loadShaderFile( gl, fileName, shader, prefix ){
+ var drawBuffersExt = gl.getExtension("WEBGL_draw_buffers");
prefix = prefix || "";
- prefix = "#extension GL_EXT_draw_buffers: enable\nprecision highp float; \n" + prefix;
- var request = new XMLHttpRequest();
+ var basePrefix = "precision highp float; \n";
+
+ if (drawBuffersExt) {
+ // Only ask GLSL to enable the extension when it is available; some
+ // browsers (notably mobile Safari) disable it when GPU capability is
+ // reduced, and requesting it regardless can cause vague shader link
+ // failures instead of falling back to the supported feature set.
+ prefix = "#extension GL_EXT_draw_buffers: enable\n" + basePrefix + prefix;
+ } else {
+ prefix = basePrefix + prefix;
+ }
+
+ var request = new XMLHttpRequest();
//Register a callback function
//
diff --git a/particleDemo.html b/particleDemo.html
index b6a4c0b..7935290 100644
--- a/particleDemo.html
+++ b/particleDemo.html
@@ -6,19 +6,29 @@
Sec3 Particle Demo
-
-
+
+
+
+
+
-
-
-
-
-
+
+
+
+
+
+