Add opacity support to Placemarks, Paths, Ellipses, Polygons, Surface…

…Images and Labels. (#40)

worldwind/src/commonMain/kotlin/earth/worldwind/draw/DrawShapeState.kt

@@ -23,6 +23,7 @@ open class DrawShapeState internal constructor() {
     var enableDepthWrite = true
     var depthOffset = 0.0
     protected val color = Color()
+    protected var opacity = 1.0f
     protected var lineWidth = 1f
     protected var texture: Texture? = null
     protected val texCoordMatrix = Matrix3()
@@ -40,6 +41,7 @@ open class DrawShapeState internal constructor() {
         enableDepthTest = true
         depthOffset = 0.0
         color.set(1f, 1f, 1f, 1f)
+        opacity = 1.0f
         lineWidth = 1f
         texture = null
         texCoordMatrix.setToIdentity()
@@ -51,6 +53,8 @@ open class DrawShapeState internal constructor() {
 
     fun color(color: Color) = apply { this.color.copy(color) }
 
+    fun opacity(opacity: Float) = apply { this.opacity = opacity }
+
     fun lineWidth(width: Float) = apply { lineWidth = width }
 
     fun texture(texture: Texture?) = apply { this.texture = texture }
@@ -69,6 +73,7 @@ open class DrawShapeState internal constructor() {
         prim.type = type
         prim.offset = offset
         prim.color.copy(color)
+        prim.opacity = opacity
         prim.lineWidth = lineWidth
         prim.texture = texture
         prim.texCoordMatrix.copy(texCoordMatrix)
@@ -82,6 +87,7 @@ open class DrawShapeState internal constructor() {
         var type = 0
         var offset = 0
         val color = Color()
+        var opacity = 1.0f
         var lineWidth = 0f
         var texture: Texture? = null
         val texCoordMatrix = Matrix3()

worldwind/src/commonMain/kotlin/earth/worldwind/draw/DrawableLines.kt

@@ -14,6 +14,7 @@ open class DrawableLines protected constructor(): Drawable {
     var vertexPoints: FloatBufferObject? = null
     val mvpMatrix = Matrix4()
     val color = Color()
+    var opacity = 1.0f
     var lineWidth = 1f
     var enableDepthTest = true
     var program: BasicShaderProgram? = null
@@ -51,6 +52,9 @@ open class DrawableLines protected constructor(): Drawable {
         // Use the leader's color.
         program.loadColor(color)
 
+        // Use the leader's opacity.
+        program.loadOpacity(opacity)
+
         // Use the leader's modelview-projection matrix.
         program.loadModelviewProjection(mvpMatrix)
 

worldwind/src/commonMain/kotlin/earth/worldwind/draw/DrawableScreenTexture.kt

@@ -14,6 +14,7 @@ import kotlin.jvm.JvmStatic
 open class DrawableScreenTexture protected constructor(): Drawable {
     val unitSquareTransform = Matrix4()
     val color = Color()
+    var opacity = 1.0f
     var enableDepthTest = true
     var program: BasicShaderProgram? = null
     var texture: Texture? = null
@@ -76,6 +77,7 @@ open class DrawableScreenTexture protected constructor(): Drawable {
 
         // Use the drawable's color.
         program.loadColor(drawable.color)
+        program.loadOpacity(drawable.opacity)
 
         // Attempt to bind the drawable's texture, configuring the shader program appropriately if there is no texture
         // or if the texture failed to bind.

worldwind/src/commonMain/kotlin/earth/worldwind/draw/DrawableShape.kt

@@ -72,6 +72,7 @@ open class DrawableShape protected constructor(): Drawable {
         for (idx in 0 until drawState.primCount) {
             val prim = drawState.prims[idx]
             program.loadColor(prim.color)
+            program.loadOpacity(prim.opacity)
             if (prim.texture?.bindTexture(dc) == true) {
                 program.loadTexCoordMatrix(prim.texCoordMatrix)
                 program.enableTexture(true)

worldwind/src/commonMain/kotlin/earth/worldwind/draw/DrawableSurfaceTexture.kt

@@ -12,6 +12,7 @@ import kotlin.jvm.JvmStatic
 open class DrawableSurfaceTexture protected constructor(): Drawable {
     val sector = Sector()
     val color = Color()
+    var opacity = 1.0f
     val texCoordMatrix = Matrix3()
     var texture: Texture? = null
     var program: SurfaceTextureProgram? = null
@@ -31,6 +32,7 @@ open class DrawableSurfaceTexture protected constructor(): Drawable {
     ) = apply {
         if (sector != null) this.sector.copy(sector) else this.sector.setEmpty()
         this.color.set(1f, 1f, 1f, 1f)
+        this.opacity = 1f
         if (texCoordMatrix != null) this.texCoordMatrix.copy(texCoordMatrix) else this.texCoordMatrix.setToIdentity()
         this.texture = texture
         this.program = program
@@ -124,6 +126,9 @@ open class DrawableSurfaceTexture protected constructor(): Drawable {
                 // Use the surface texture's RGBA color.
                 program.loadColor(texture.color)
 
+                // Use the surface texture's opacity.
+                program.loadOpacity(texture.opacity)
+
                 // Draw the terrain as triangles.
                 terrain.drawTriangles(dc)
             }

worldwind/src/commonMain/kotlin/earth/worldwind/render/program/BasicShaderProgram.kt

@@ -34,6 +34,7 @@ open class BasicShaderProgram : AbstractShaderProgram() {
             uniform bool enablePickMode;
             uniform bool enableTexture;
             uniform vec4 color;
+            uniform float opacity;
             uniform sampler2D texSampler;
 
             varying vec2 texCoord;
@@ -47,10 +48,10 @@ open class BasicShaderProgram : AbstractShaderProgram() {
                     gl_FragColor = color * texMask;
                 } else if (!enablePickMode && enableTexture) {
                     /* Modulate the RGBA color with the 2D texture's RGBA color. */
-                    gl_FragColor = color * texture2D(texSampler, texCoord);
+                    gl_FragColor = color * texture2D(texSampler, texCoord) * opacity;
                 } else {
                     /* Return the RGBA color as-is. */
-                    gl_FragColor = color;
+                    gl_FragColor = color * opacity;
                 }
             }
         """.trimIndent()
@@ -62,12 +63,14 @@ open class BasicShaderProgram : AbstractShaderProgram() {
     protected val mvpMatrix = Matrix4()
     protected val texCoordMatrix = Matrix3()
     protected val color = Color()
+    protected var opacity = 1.0f
     protected var enablePickModeId = KglUniformLocation.NONE
     protected var enableTextureId = KglUniformLocation.NONE
     protected var mvpMatrixId = KglUniformLocation.NONE
     protected var texCoordMatrixId = KglUniformLocation.NONE
     protected var texSamplerId = KglUniformLocation.NONE
     protected var colorId = KglUniformLocation.NONE
+    protected var opacityId = KglUniformLocation.NONE
     private val array = FloatArray(16)
 
     override fun initProgram(dc: DrawContext) {
@@ -85,6 +88,8 @@ open class BasicShaderProgram : AbstractShaderProgram() {
         colorId = gl.getUniformLocation(program, "color")
         val alpha = color.alpha
         gl.uniform4f(colorId, color.red * alpha, color.green * alpha, color.blue * alpha, alpha)
+        opacityId = gl.getUniformLocation(program, "opacity")
+        gl.uniform1f(opacityId, opacity)
         texSamplerId = gl.getUniformLocation(program, "texSampler")
         gl.uniform1i(texSamplerId, 0) // GL_TEXTURE0
     }
@@ -124,4 +129,11 @@ open class BasicShaderProgram : AbstractShaderProgram() {
             gl.uniform4f(colorId, color.red * alpha, color.green * alpha, color.blue * alpha, alpha)
         }
     }
+
+    fun loadOpacity(opacity: Float) {
+        if (this.opacity != opacity) {
+            this.opacity = opacity
+            gl.uniform1f(opacityId, opacity)
+        }
+    }
 }

worldwind/src/commonMain/kotlin/earth/worldwind/render/program/SurfaceTextureProgram.kt

@@ -45,6 +45,7 @@ open class SurfaceTextureProgram : AbstractShaderProgram() {
             uniform bool enablePickMode;
             uniform bool enableTexture;
             uniform vec4 color;
+            uniform float opacity;
             uniform sampler2D texSampler;
 
             varying vec2 texCoord;
@@ -65,10 +66,10 @@ open class SurfaceTextureProgram : AbstractShaderProgram() {
                 } else if (!enablePickMode && enableTexture) {
                     /* Using the first texture coordinate, modulate the RGBA color with the 2D texture's RGBA color. Finally,
                        modulate by the tile mask to suppress fragments outside the surface tile. */
-                    gl_FragColor = color * texture2D(texSampler, texCoord) * tileMask;
+                    gl_FragColor = color * texture2D(texSampler, texCoord) * opacity * tileMask;
                 } else {
                     /* Modulate the RGBA color by the tile mask to suppress fragments outside the surface tile. */
-                    gl_FragColor = color * tileMask;
+                    gl_FragColor = color * opacity * tileMask;
                 }
             }
         """.trimIndent()
@@ -83,9 +84,11 @@ open class SurfaceTextureProgram : AbstractShaderProgram() {
     protected var texCoordMatrixId = KglUniformLocation.NONE
     protected var texSamplerId = KglUniformLocation.NONE
     protected var colorId = KglUniformLocation.NONE
+    protected var opacityId = KglUniformLocation.NONE
     private val mvpMatrixArray = FloatArray(16)
     private val texCoordMatrixArray = FloatArray(9 * 2)
     private val color = Color()
+    private var opacity = 1.0f
 
     override fun initProgram(dc: DrawContext) {
         super.initProgram(dc)
@@ -103,6 +106,8 @@ open class SurfaceTextureProgram : AbstractShaderProgram() {
         colorId = gl.getUniformLocation(program, "color")
         color.set(1f, 1f, 1f, 1f) // opaque white
         gl.uniform4f(colorId, color.red, color.green, color.blue, color.alpha)
+        opacityId = gl.getUniformLocation(program, "opacity")
+        gl.uniform1f(opacityId, opacity)
         texSamplerId = gl.getUniformLocation(program, "texSampler")
         gl.uniform1i(texSamplerId, 0) // GL_TEXTURE0
     }
@@ -123,10 +128,17 @@ open class SurfaceTextureProgram : AbstractShaderProgram() {
     }
 
     fun loadColor(color: Color) {
-        if (this.color != color) { // suppress unnecessary writes to GLSL uniform variables
+        if (this.color != color) {
             this.color.copy(color)
-            val a: Float = color.alpha
-            gl.uniform4f(colorId, color.red * a, color.green * a, color.blue * a, a)
+            val alpha = color.alpha
+            gl.uniform4f(colorId, color.red * alpha, color.green * alpha, color.blue * alpha, alpha)
+        }
+    }
+
+    fun loadOpacity(opacity: Float) {
+        if (this.opacity != opacity) {
+            this.opacity = opacity
+            gl.uniform1f(opacityId, opacity)
         }
     }
 }

worldwind/src/commonMain/kotlin/earth/worldwind/shape/Ellipse.kt

@@ -311,6 +311,7 @@ open class Ellipse @JvmOverloads constructor(
 
         // Configure the drawable to display the shape's interior.
         drawState.color(if (rc.isPickMode) pickColor else activeAttributes.interiorColor)
+        drawState.opacity(if (rc.isPickMode) 1f else rc.currentLayer.opacity)
         drawState.texCoordAttrib(2 /*size*/, 12 /*offset in bytes*/)
         val top = drawState.elementBuffer!!.ranges[TOP_RANGE]!!
         drawState.drawElements(GL_TRIANGLE_STRIP, top.length, GL_UNSIGNED_SHORT, top.lower * 2 /*offset*/)
@@ -336,13 +337,15 @@ open class Ellipse @JvmOverloads constructor(
 
         // Configure the drawable to display the shape's outline.
         drawState.color(if (rc.isPickMode) pickColor else activeAttributes.outlineColor)
+        drawState.opacity(if (rc.isPickMode) 1f else rc.currentLayer.opacity)
         drawState.lineWidth(activeAttributes.outlineWidth)
         drawState.texCoordAttrib(1 /*size*/, 20 /*offset in bytes*/)
         val outline = drawState.elementBuffer!!.ranges[OUTLINE_RANGE]!!
         drawState.drawElements(GL_LINE_LOOP, outline.length, GL_UNSIGNED_SHORT, outline.lower * 2 /*offset*/)
         if (activeAttributes.isDrawVerticals && isExtrude) {
             val side = drawState.elementBuffer!!.ranges[SIDE_RANGE]!!
             drawState.color(if (rc.isPickMode) pickColor else activeAttributes.outlineColor)
+            drawState.opacity(if (rc.isPickMode) 1f else rc.currentLayer.opacity)
             drawState.lineWidth(activeAttributes.outlineWidth)
             drawState.texture(null)
             drawState.drawElements(GL_LINES, side.length, GL_UNSIGNED_SHORT, side.lower * 2)

worldwind/src/commonMain/kotlin/earth/worldwind/shape/Label.kt

@@ -125,9 +125,7 @@ open class Label @JvmOverloads constructor(
         val drawableCount = rc.drawableCount
         if (rc.isPickMode) {
             renderData.pickedObjectId = rc.nextPickedObjectId()
-            PickedObject.identifierToUniqueColor(
-                renderData.pickedObjectId, renderData.pickColor
-            )
+            PickedObject.identifierToUniqueColor(renderData.pickedObjectId, renderData.pickColor)
         }
 
         // Enqueue drawables for processing on the OpenGL thread.
@@ -200,6 +198,7 @@ open class Label @JvmOverloads constructor(
         // in the texture's color.
         if (rc.isPickMode) drawable.color.copy(renderData.pickColor)
         else drawable.color.set(1f, 1f, 1f, 1f)
+        drawable.opacity = if (rc.isPickMode) 1f else rc.currentLayer.opacity
         drawable.texture = texture
         drawable.enableDepthTest = activeAttributes.isDepthTest
 

worldwind/src/commonMain/kotlin/earth/worldwind/shape/Path.kt

@@ -115,6 +115,7 @@ open class Path @JvmOverloads constructor(
         // drawn indirectly offscreen framebuffer appear thinner when sampled as a texture.
         if (activeAttributes.isDrawOutline) {
             drawState.color(if (rc.isPickMode) pickColor else activeAttributes.outlineColor)
+            drawState.opacity(if (rc.isPickMode) 1f else rc.currentLayer.opacity)
             drawState.lineWidth(activeAttributes.outlineWidth + if (isSurfaceShape) 0.5f else 0f)
             drawState.drawElements(
                 GL_LINE_STRIP, outlineElements.size,
@@ -128,6 +129,7 @@ open class Path @JvmOverloads constructor(
         // Configure the drawable to display the shape's extruded verticals.
         if (activeAttributes.isDrawOutline && activeAttributes.isDrawVerticals && isExtrude) {
             drawState.color(if (rc.isPickMode) pickColor else activeAttributes.outlineColor)
+            drawState.opacity(if (rc.isPickMode) 1f else rc.currentLayer.opacity)
             drawState.lineWidth(activeAttributes.outlineWidth)
             drawState.drawElements(
                 GL_LINES, verticalElements.size,
@@ -138,6 +140,7 @@ open class Path @JvmOverloads constructor(
         // Configure the drawable to display the shape's extruded interior.
         if (activeAttributes.isDrawInterior && isExtrude) {
             drawState.color(if (rc.isPickMode) pickColor else activeAttributes.interiorColor)
+            drawState.opacity(if (rc.isPickMode) 1f else rc.currentLayer.opacity)
             drawState.drawElements(
                 GL_TRIANGLE_STRIP, interiorElements.size,
                 GL_UNSIGNED_INT, 0

worldwind/src/commonMain/kotlin/earth/worldwind/shape/Placemark.kt

@@ -413,6 +413,7 @@ open class Placemark @JvmOverloads constructor(
         // the active attributes' image source and its associated tex coord transform. If the texture is not specified
         // or not available, draw a simple colored square.
         drawable.color.copy(if (rc.isPickMode) pickColor else activeAttributes.imageColor)
+        drawable.opacity = if (rc.isPickMode) 1f else rc.currentLayer.opacity
         drawable.texture = activeTexture
         drawable.enableDepthTest = activeAttributes.isDepthTest
     }
@@ -437,6 +438,7 @@ open class Placemark @JvmOverloads constructor(
         // color for drawing, specifying white for normal drawing ensures the color multiplication in the shader results
         // in the texture's color.
         if (rc.isPickMode) drawable.color.copy(pickColor) else drawable.color.set(1f, 1f, 1f, 1f)
+        drawable.opacity = if (rc.isPickMode) 1f else rc.currentLayer.opacity
         drawable.texture = labelTexture
         drawable.enableDepthTest = activeAttributes.labelAttributes.isDepthTest
     }
@@ -475,6 +477,7 @@ open class Placemark @JvmOverloads constructor(
         // Configure the drawable according to the placemark's active leader attributes. Use a color appropriate for the
         // pick mode. When picking use a unique color associated with the picked object ID.
         drawable.color.copy(if (rc.isPickMode) pickColor else activeAttributes.leaderAttributes.outlineColor)
+        drawable.opacity = if (rc.isPickMode) 1f else rc.currentLayer.opacity
         drawable.lineWidth = activeAttributes.leaderAttributes.outlineWidth
         drawable.enableDepthTest = activeAttributes.leaderAttributes.isDepthTest
     }

worldwind/src/commonMain/kotlin/earth/worldwind/shape/Polygon.kt

@@ -203,6 +203,7 @@ open class Polygon @JvmOverloads constructor(
 
         // Configure the drawable to display the shape's interior top.
         drawState.color(if (rc.isPickMode) pickColor else activeAttributes.interiorColor)
+        drawState.opacity(if (rc.isPickMode) 1f else rc.currentLayer.opacity)
         drawState.texCoordAttrib(2 /*size*/, 12 /*offset in bytes*/)
         drawState.drawElements(GL_TRIANGLES, topElements.size, GL_UNSIGNED_INT, 0 /*offset*/)
 
@@ -228,6 +229,7 @@ open class Polygon @JvmOverloads constructor(
 
         // Configure the drawable to display the shape's outline.
         drawState.color(if (rc.isPickMode) pickColor else activeAttributes.outlineColor)
+        drawState.opacity(if (rc.isPickMode) 1f else rc.currentLayer.opacity)
         drawState.lineWidth(activeAttributes.outlineWidth)
         drawState.texCoordAttrib(1 /*size*/, 20 /*offset in bytes*/)
         drawState.drawElements(
@@ -238,6 +240,7 @@ open class Polygon @JvmOverloads constructor(
         // Configure the drawable to display the shape's extruded verticals.
         if (activeAttributes.isDrawVerticals && isExtrude) {
             drawState.color(if (rc.isPickMode) pickColor else activeAttributes.outlineColor)
+            drawState.opacity(if (rc.isPickMode) 1f else rc.currentLayer.opacity)
             drawState.lineWidth(activeAttributes.outlineWidth)
             drawState.texture(null)
             drawState.drawElements(

worldwind/src/commonMain/kotlin/earth/worldwind/shape/SurfaceImage.kt

@@ -20,6 +20,7 @@ open class SurfaceImage(sector: Sector, var imageSource: ImageSource): AbstractS
         val program = getShaderProgram(rc)
         val pool = rc.getDrawablePool<DrawableSurfaceTexture>()
         val drawable = DrawableSurfaceTexture.obtain(pool).set(program, sector, texture, texture.coordTransform)
+        drawable.opacity = if (rc.isPickMode) 1f else rc.currentLayer.opacity
         rc.offerSurfaceDrawable(drawable, 0.0 /*z-order*/)
 
         // Enqueue a picked object that associates the drawable surface texture with this surface image.