Merge pull request #47 from dmurdoch/transparency

Transparency

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: rgl2gltf
 Type: Package
 Title: Read and Write '.gltf' and '.glb' Files
-Version: 1.0.3
+Version: 1.0.4
 Authors@R: c(person("Duncan", "Murdoch", role = c("aut", "cre"),
                      email = "murdoch.duncan@gmail.com"),
              person("Morten S.", "Mikkelsen", role = c("cph")))
@@ -24,5 +24,5 @@ Suggests:
     png,
     jpeg
 VignetteBuilder: knitr, rmarkdown
-RoxygenNote: 7.2.1
+RoxygenNote: 7.2.3
 Roxygen: list(markdown = TRUE)

NEWS.md

@@ -1,3 +1,7 @@
+# rgl2gltf 1.0.4
+
+* Support transparency.
+
 # rgl2gltf 1.0.3
 
 * Added print support for sparse accessors; `rgl` added

R/PBR.R

@@ -96,6 +96,16 @@ setPBRshaders <- function(gltf, gltfMat,
   }
   defines[["MANUAL_SRGB"]] <- 1
 
+  if (is.null(alphaMode <- gltfMat$alphaMode))
+    alphaMode <- "OPAQUE"
+  if (is.null(alphaCutoff <- gltfMat$alphaCutoff))
+    alphaCutoff <- 0.5
+
+  if (alphaMode != "MASK")
+    alphaCutoff <- -1
+
+  uniforms[["u_alphaCutoff"]] <- alphaCutoff
+
   if (length(defines))
     defines <- paste("#define", names(defines), unlist(defines))
   else

R/gltfObj.R

@@ -447,6 +447,8 @@ Gltf <- R6Class("gltf",
         result <- list()
       else {
         material <- self$getMaterial(n)
+        if (is.null(alphaMode <- material$alphaMode))
+          alphaMode <- "OPAQUE"
         result <- list(color = "white", alpha = 1)
         if (!is.null(pbrm <- material$pbrMetallicRoughness)) {
           if (!is.null(col <- unlist(pbrm$baseColorFactor))) {
@@ -459,6 +461,10 @@ Gltf <- R6Class("gltf",
             result$texture <- texturefile
             texture <- self$getTexture(texnum)
             result$gltftexCoord <- texture$texCoord
+            if (alphaMode == "OPAQUE")
+              result$textype <- "rgb"
+            else
+              result$textype <- "rgba"
           }
         }
         if (!is.null(col <- unlist(material$emissiveFactor)))
@@ -476,6 +482,8 @@ Gltf <- R6Class("gltf",
           result <- lapply(result, unlist)
         } else
           result$specular <- "gray10"
+        if (alphaMode == "OPAQUE")
+          result$alpha <- 1
       }
       result
     },

R/gltfWidget.R

@@ -1,4 +1,4 @@
-animationDependency <- makeDependency(name = "gltfAnimate",
+animationDependency <- function() makeDependency(name = "gltfAnimate",
                                                      src = "javascript/gltfAnimate",
                                                      script = "gltfAnimate.js",
                                                      package = "rgl2gltf",
@@ -35,7 +35,7 @@ animationControl <- function(gltf, ani = 0, value = gltf$timerange(ani)[1], tran
                  value = value,
                  animation = animation,
                  buffer = buffer$as.list(),
-                 dependencies = list(animationDependency)),
+                 dependencies = list(animationDependency())),
             class = "rglControl")
 }
 
@@ -52,7 +52,7 @@ weightedControl <- function(subid, nodes, weights, translations,
                  nodes = unname(nodes),
                  weights = unname(weights),
                  backtransform = backtransforms,
-                 dependencies = list(animationDependency)),
+                 dependencies = list(animationDependency())),
             class = "rglControl")
 }
 
@@ -61,7 +61,7 @@ skeletonControl <- function(subid) {
   structure(list(type = "rgl2gltfSkeleton",
                  value = 0,
                  subid = unname(subid),
-                 dependencies = list(animationDependency)),
+                 dependencies = list(animationDependency())),
             class = "rglControl")
 }
 
@@ -76,7 +76,7 @@ shaderControl <- function(id, joints, usedjoints, backtransform) {
                  id = unname(id),
                  joints = unname(joints[keep]),
                  backtransform = backtransforms,
-                 dependencies = list(animationDependency)),
+                 dependencies = list(animationDependency())),
             class = "rglControl")
 }
 

README.Rmd

@@ -76,15 +76,15 @@ are not included in the package tarball.
 Briefly,
 
 - `2CylinderEngine.glb` was produced by Okino Computer Graphics.
+- `AlphaBlendModeTest.glb`, `NormalTangentTest.glb` and `NormalTangentMirrorTest.glb` were created
+by Ed Mackey and are owned by Analytical Graphics, Inc., licensed under
+CC-BY 4.0 https://creativecommons.org/licenses/by/4.0/.
 - `AntiqueCamera.glb` was produced by Maximilian Kamps and UX3D.
 - `Avocado.glb` was produced by Microsoft.
 - `BarramundiFish.glb` was produced by Microsoft.
-- `BoxAnimated.glb` was produced by Cesium.
+- `BoxAnimated.glb` and `RiggedSimple.glb` were produced by Cesium.
 - `BrainStem.glb` was created by Keith Hunter and is owned by Smith Micro Software, Inc. 
 - `DamagedHelmet.glb` was created by theblueturtle_.
-- `NormalTangentTest.glb` and `NormalTangentMirrorTest.glb` were created
-by Ed Mackey and are owned by Analytical Graphics, Inc., licensed under
-CC-BY 4.0 https://creativecommons.org/licenses/by/4.0/.
 
 Files `src/mikktspace.c` and `src/mikktspace.h` are written by Morten
 S. Mikkelsen and used under the permissive license included

README.md

@@ -56,18 +56,18 @@ included in the package tarball.
 
 Briefly,
 
--   `2CylinderEngine.glb` was produced by Okino Computer Graphics.
--   `AntiqueCamera.glb` was produced by Maximilian Kamps and UX3D.
--   `Avocado.glb` was produced by Microsoft.
--   `BarramundiFish.glb` was produced by Microsoft.
--   `BoxAnimated.glb` was produced by Cesium.
--   `BrainStem.glb` was created by Keith Hunter and is owned by Smith
-    Micro Software, Inc. 
--   `DamagedHelmet.glb` was created by theblueturtle\_.
--   `NormalTangentTest.glb` and `NormalTangentMirrorTest.glb` were
-    created by Ed Mackey and are owned by Analytical Graphics, Inc.,
-    licensed under CC-BY 4.0
-    <https://creativecommons.org/licenses/by/4.0/>.
+- `2CylinderEngine.glb` was produced by Okino Computer Graphics.
+- `AlphaBlendModeTest.glb`, `NormalTangentTest.glb` and
+  `NormalTangentMirrorTest.glb` were created by Ed Mackey and are owned
+  by Analytical Graphics, Inc., licensed under CC-BY 4.0
+  <https://creativecommons.org/licenses/by/4.0/>.
+- `AntiqueCamera.glb` was produced by Maximilian Kamps and UX3D.
+- `Avocado.glb` was produced by Microsoft.
+- `BarramundiFish.glb` was produced by Microsoft.
+- `BoxAnimated.glb` and `RiggedSimple.glb` were produced by Cesium.
+- `BrainStem.glb` was created by Keith Hunter and is owned by Smith
+  Micro Software, Inc. 
+- `DamagedHelmet.glb` was created by theblueturtle\_.
 
 Files `src/mikktspace.c` and `src/mikktspace.h` are written by Morten S.
 Mikkelsen and used under the permissive license included within them,

inst/shaders/pbr-frag.glsl

@@ -53,6 +53,8 @@ uniform float u_OcclusionStrength;
 uniform vec2 u_MetallicRoughnessValues;
 varying vec4 vCol;
 
+uniform float u_alphaCutoff;
+
 // debugging flags used for shader output of intermediate PBR variables
 uniform vec4 u_ScaleDiffBaseMR;
 uniform vec4 u_ScaleFGDSpec;
@@ -329,5 +331,9 @@ void main()
     color = mix(color, vec3(metallic), u_ScaleDiffBaseMR.z);
     color = mix(color, vec3(perceptualRoughness), u_ScaleDiffBaseMR.w);
 
-    gl_FragColor = vec4(pow(color,vec3(1.0/2.2)), baseColor.a);
+    float alpha = baseColor.a;
+    if (u_alphaCutoff >= 0.0)
+      alpha = alpha < u_alphaCutoff ? 0.0 : 1.0;
+
+    gl_FragColor = vec4(pow(color,vec3(1.0/2.2)), alpha);
 }