package rename + storage backend abstraction

src/main/resources/assets/zenith/shaders/lod/gl46/cmdgen.comp

@@ -0,0 +1,74 @@
+#version 460
+#extension GL_ARB_gpu_shader_int64 : enable
+
+layout(local_size_x = 128, local_size_y = 1, local_size_x = 1) in;
+
+#import <zenith:lod/gl46/quad_format.glsl>
+#import <zenith:lod/gl46/bindings.glsl>
+#import <zenith:lod/gl46/frustum.glsl>
+#import <zenith:lod/gl46/section.glsl>
+
+//https://github.com/KhronosGroup/GLSL/blob/master/extensions/ext/GL_EXT_shader_16bit_storage.txt
+// adds support for uint8_t which can use for compact visibility buffer
+
+
+
+/*
+    uint  count;
+    uint  instanceCount;
+    uint  firstIndex;
+    int  baseVertex;
+    uint  baseInstance;
+    */
+
+uint encodeLocalLodPos(uint detail, ivec3 pos) {
+    uvec3 detla = (pos - (baseSectionPos >> detail))&((1<<9)-1);
+    return (detail<<29)|(detla.x<<20)|(detla.y<<11)|(detla.z<<2);
+}
+
+
+//TODO: swap to a multidraw indirect counted
+
+void main() {
+    if (gl_GlobalInvocationID.x >= sectionCount) {
+        return;
+    }
+    SectionMeta meta = sectionData[gl_GlobalInvocationID.x];
+    uint detail = extractDetail(meta);
+    ivec3 ipos = extractPosition(meta);
+
+    vec3 cornerPos = vec3(((ipos<<detail)-baseSectionPos)<<5)-cameraSubPos;
+
+
+    //Check the occlusion data from last frame
+    bool shouldRender = visibilityData[gl_GlobalInvocationID.x] == frameId - 1;
+
+    //Clear the occlusion data (not strictly? needed? i think???)
+    //visibilityData[gl_GlobalInvocationID.x] = 0;
+
+    //TODO: need to make it check that only if it was also in the frustum last frame does it apply the visibilityData check!
+    // this fixes temporal coherance
+
+    //This prevents overflow of the relative position encoder
+    if (shouldRender) {
+        shouldRender = !any(lessThan(ivec3(254), abs(ipos-(baseSectionPos>>detail))));
+    }
+
+    if (shouldRender) {
+        DrawCommand cmd;
+        cmd.count = extractQuadCount(meta) * 6;
+        cmd.instanceCount = 1;
+        cmd.firstIndex = 0;
+        cmd.baseVertex = int(extractQuadStart(meta))<<2;
+        cmd.baseInstance = encodeLocalLodPos(detail, ipos);
+        cmdBuffer[gl_GlobalInvocationID.x] = cmd;
+    } else {
+        DrawCommand cmd;
+        cmd.count = 0;
+        cmd.instanceCount = 0;
+        cmd.firstIndex = 0;
+        cmd.baseVertex = 0;
+        cmd.baseInstance = 0;
+        cmdBuffer[gl_GlobalInvocationID.x] = cmd;
+    }
+}