[orx-mesh, orx-mesh-generator, orx-obj-loader] Add decal and tangent tools

2024-09-25 09:51:46 +02:00
parent fb3bb6f7a6
commit e016891b1d
28 changed files with 1072 additions and 82 deletions
--- a/orx-mesh-generators/src/jvmDemo/kotlin/decal/DemoDecal02.kt
+++ b/orx-mesh-generators/src/jvmDemo/kotlin/decal/DemoDecal02.kt
@@ -0,0 +1,86 @@
+package decal
+
+import org.openrndr.application
+import org.openrndr.draw.DrawPrimitive
+import org.openrndr.draw.isolated
+import org.openrndr.draw.shadeStyle
+import org.openrndr.extra.camera.Orbital
+import org.openrndr.extra.objloader.loadOBJMeshData
+import org.openrndr.extra.mesh.toVertexBuffer
+import org.openrndr.extra.meshgenerators.decal.decal
+import org.openrndr.math.Vector3
+import org.openrndr.math.transforms.buildTransform
+import java.io.File
+import kotlin.math.PI
+
+/**
+ * Demonstrate decal generation and rendering
+ */
+fun main() {
+    application {
+        configure {
+            width = 720
+            height = 720
+        }
+        program {
+            /** base object */
+            val obj = loadOBJMeshData(File("demo-data/obj-models/suzanne/Suzanne.obj"))
+                .toMeshData() // convert from CompoundMeshData to MeshData
+                .triangulate() // convert to triangles, we need this for the decal generation steps
+
+            /** object [VertexBuffer] */
+            val objVB = obj.toVertexBuffer()
+
+
+            /** positions for the decal projectors */
+            val decalPositions = listOf(
+                Vector3(0.35, 0.245, 0.8),
+                Vector3(-0.35, 0.245, 0.8)
+            )
+
+            /** decal vertex buffers */
+            val decalVBs = decalPositions.map {
+                val projector = buildTransform {
+                    translate(it)
+                }
+                val decal = obj.decal(projector, Vector3(2.0, 2.0, 0.5))
+                val vb = decal.toVertexBuffer()
+                vb
+            }
+
+            extend(Orbital()) {
+                eye = Vector3(0.0, 0.0, 2.0)
+            }
+            extend {
+                /* draw the base mesh */
+                drawer.isolated {
+                    drawer.shadeStyle = shadeStyle {
+                        fragmentTransform = """x_fill.rgb = vec3(v_viewNormal * 0.5 + 0.5); """
+                    }
+                    drawer.vertexBuffer(objVB, DrawPrimitive.TRIANGLES)
+                }
+
+                /* draw the decals */
+                drawer.isolated {
+                    for ((index, decal) in decalVBs.withIndex()) {
+                        /* offset the projection transform to avoid z-fighting */
+                        drawer.projection = buildTransform {
+                            translate(0.0, 0.0, -1e-4)
+                        } * drawer.projection
+
+                        /* draw effects on the decal geometry */
+                        drawer.shadeStyle = shadeStyle {
+                            fragmentTransform = """
+                                float d = length(va_texCoord0.xy - vec2(0.5));
+                                float sd = smoothstep(-0.01, 0.01, cos(p_time + d * 3.1415 * 2.0 * 10.0));
+                                float l = max(0.0, va_normal.z);
+                                x_fill = vec4(0.0, 0.0, 0.0, l * sd * 0.5); """
+                            parameter("time", seconds * PI * 2 + index * PI)
+                        }
+                        drawer.vertexBuffer(decal, DrawPrimitive.TRIANGLES)
+                    }
+                }
+            }
+        }
+    }
+}