From 8ef12ff1ac3d6e6d8c33c5f60860298052f6c660 Mon Sep 17 00:00:00 2001
From: Swung0x48 <swung0x48@outlook.com>
Date: Mon, 21 Apr 2025 12:25:45 +0800
Subject: [PATCH] [Fix] (multidraw: compute): restore original program

---
 src/main/cpp/gl/multidraw.cpp               | 13 +++----------
 src/main/cpp/shaders/multidraw_compute.comp | 16 +++-------------
 2 files changed, 6 insertions(+), 23 deletions(-)

diff --git a/src/main/cpp/gl/multidraw.cpp b/src/main/cpp/gl/multidraw.cpp
index fa02f85..6fb03c3 100644
--- a/src/main/cpp/gl/multidraw.cpp
+++ b/src/main/cpp/gl/multidraw.cpp
@@ -267,17 +267,8 @@ void main() {
     if (outIdx >= prefixSums[prefixSums.length() - 1])
         return;
 
-    // bisect to find out draw call #
+    // Find out draw call #
     int low = 0;
-//    int high = draws.length() - 1;
-//    while (low < high) {
-//        int mid = (low + high + 1) / 2;
-//        if (prefixSums[mid] <= outIdx) {
-//            low = mid;
-//        } else {
-//            high = mid - 1;
-//        }
-//    }
     int l = draws.length() - 1;
     for (low = 0; low < l; ++low) {
         if (prefixSums[low] > outIdx) {
@@ -433,6 +424,8 @@ GLAPI GLAPIENTRY void mg_glMultiDrawElementsBaseVertex_compute(
 
     // Bind index buffer and do draw
     LOG_D("draw")
+    GLES.glUseProgram(prev_program);
+    CHECK_GL_ERROR_NO_INIT
     GLES.glBindBuffer(GL_VERTEX_ARRAY, prev_vb);
     CHECK_GL_ERROR_NO_INIT
     GLES.glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, g_outputibo);
diff --git a/src/main/cpp/shaders/multidraw_compute.comp b/src/main/cpp/shaders/multidraw_compute.comp
index a4f4123..1393983 100644
--- a/src/main/cpp/shaders/multidraw_compute.comp
+++ b/src/main/cpp/shaders/multidraw_compute.comp
@@ -18,20 +18,10 @@ layout(std430, binding = 3) writeonly buffer Output { uint out_indices[]; };
 void main() {
     uint outIdx = gl_GlobalInvocationID.x;
     if (outIdx >= prefixSums[prefixSums.length() - 1])
-        return;
+    return;
 
-    // bisect to find out draw call #
+    // Find out draw call #
     int low = 0;
-//    int high = draws.length() - 1;
-//    while (low < high) {
-//        int mid = (low + )
-//        int mid = (low + high + 1) / 2;
-//        if (prefixSums[mid] <= outIdx) {
-//            low = mid;
-//        } else {
-//            high = mid - 1;
-//        }
-//    }
     int l = draws.length() - 1;
     for (low = 0; low < l; ++low) {
         if (prefixSums[low] > outIdx) {
@@ -41,7 +31,7 @@ void main() {
 
     // figure out which index to take
     DrawCommand cmd = draws[low];
-    uint localIdx = outIdx - prefixSums[low];
+    uint localIdx = outIdx - ((low == 0) ? 0u : (prefixSums[low - 1]));
     uint inIndex = localIdx + cmd.firstIndex;
 
     // Write out