[Feat] (...): Add "DrawElements" multi-draw mode.

src/main/cpp/config/settings.cpp

@@ -42,7 +42,7 @@ void init_settings() {
         enableExtComputeShader = 0;
     if (enableCompatibleMode < 0 || enableCompatibleMode > 1)
         enableCompatibleMode = 0;
-    if ((int)multidrawMode < 0 || (int)multidrawMode > 3)
+    if ((int)multidrawMode < 0 || (int)multidrawMode > 4)
         multidrawMode = multidraw_mode_t::Auto;
 
     // 1205
@@ -138,6 +138,9 @@ void init_settings() {
         case multidraw_mode_t::PreferMultidrawIndirect:
             draw_mode_str = "Multidraw indirect";
             break;
+        case multidraw_mode_t::DrawElements:
+            draw_mode_str = "DrawElements";
+            break;
         case multidraw_mode_t::Auto:
             draw_mode_str = "Auto";
             break;
@@ -166,8 +169,13 @@ void init_settings_post() {
     switch (global_settings.multidraw_mode) {
         case multidraw_mode_t::PreferIndirect:
             LOG_V("multidrawMode = PreferIndirect")
+            if (indirect) {
                 global_settings.multidraw_mode = multidraw_mode_t::PreferIndirect;
                 LOG_V("    -> Indirect (OK)")
+            } else {
+                global_settings.multidraw_mode = multidraw_mode_t::DrawElements;
+                LOG_V("    -> DrawElements (Preferred not supported, falling back)")
+            }
             break;
         case multidraw_mode_t::PreferBaseVertex:
             LOG_V("multidrawMode = PreferUnroll")
@@ -177,20 +185,30 @@ void init_settings_post() {
             } else if (multidraw) {
                 global_settings.multidraw_mode = multidraw_mode_t::PreferMultidrawIndirect;
                 LOG_V("    -> MultidrawIndirect (Preferred not supported, falling back)")
-            } else {
+            } else if (indirect) {
                 global_settings.multidraw_mode = multidraw_mode_t::PreferIndirect;
                 LOG_V("    -> Indirect (Preferred not supported, falling back)")
+            } else {
+                global_settings.multidraw_mode = multidraw_mode_t::DrawElements;
+                LOG_V("    -> DrawElements (Preferred not supported, falling back)")
             }
             break;
+        case multidraw_mode_t::DrawElements:
+            LOG_V("multidrawMode = DrawElements")
+            global_settings.multidraw_mode = multidraw_mode_t::DrawElements;
+            break;
         case multidraw_mode_t::Auto:
         default:
             LOG_V("multidrawMode = Auto")
             if (multidraw) {
                 global_settings.multidraw_mode = multidraw_mode_t::PreferMultidrawIndirect;
                 LOG_V("    -> MultidrawIndirect")
-            } else {
+            } else if (indirect) {
                 global_settings.multidraw_mode = multidraw_mode_t::PreferIndirect;
-                LOG_V("    -> Indirect")
+                LOG_V("    -> Indirect (Preferred not supported, falling back)")
+            } else {
+                global_settings.multidraw_mode = multidraw_mode_t::DrawElements;
+                LOG_V("    -> DrawElements (Preferred not supported, falling back)")
             }
             break;
     }

src/main/cpp/config/settings.h

@@ -15,7 +15,8 @@ enum class multidraw_mode_t: int {
     Auto = 0,
     PreferIndirect,
     PreferBaseVertex,
-    PreferMultidrawIndirect
+    PreferMultidrawIndirect,
+    DrawElements
 };
 
 struct global_settings_t {
@@ -25,7 +26,7 @@ struct global_settings_t {
     int ext_compute_shader; // 0, 1
     size_t max_glsl_cache_size; // 0~
     int enable_compatible_mode; // 0, 1
-    multidraw_mode_t multidraw_mode; // 0, 1, 2, 3
+    multidraw_mode_t multidraw_mode; // 0, 1, 2, 3, 4
 };
 
 extern struct global_settings_t global_settings;

src/main/cpp/gl/drawing.cpp

@@ -12,8 +12,6 @@ static bool g_indirect_cmds_inited = false;
 static GLsizei g_cmdbufsize = 0;
 GLuint g_indirectbuffer = 0;
 
-#define DRAW_INDIRECT
-
 void prepare_indirect_buffer(const GLsizei *counts, GLenum type, const void *const *indices,
                              GLsizei primcount, const GLint *basevertex) {
     if (!g_indirect_cmds_inited) {
@@ -74,6 +72,91 @@ void prepare_indirect_buffer(const GLsizei *counts, GLenum type, const void *con
     GLES.glUnmapBuffer(GL_DRAW_INDIRECT_BUFFER);
 }
 
+void mg_glMultiDrawElementsBaseVertex_drawelements(GLenum mode, GLsizei* counts, GLenum type, const void* const* indices, GLsizei primcount, const GLint* basevertex) {
+    LOG()
+
+    GLint prevElementBuffer;
+    GLES.glGetIntegerv(GL_ELEMENT_ARRAY_BUFFER_BINDING, &prevElementBuffer);
+
+    for (GLsizei i = 0; i < primcount; ++i) {
+        if (counts[i] <= 0) continue;
+
+        GLsizei currentCount = counts[i];
+        const GLvoid *currentIndices = indices[i];
+        GLint currentBaseVertex = basevertex[i];
+
+        size_t indexSize;
+        switch (type) {
+            case GL_UNSIGNED_INT:  indexSize = sizeof(GLuint);   break;
+            case GL_UNSIGNED_SHORT: indexSize = sizeof(GLushort); break;
+            case GL_UNSIGNED_BYTE:  indexSize = sizeof(GLubyte);  break;
+            default: return;
+        }
+
+        GLuint tempBuffer;
+        GLES.glGenBuffers(1, &tempBuffer);
+        GLES.glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, tempBuffer);
+
+        void *srcData = nullptr;
+        void *tempIndices = malloc(currentCount * indexSize);
+        if (!tempIndices) {
+            GLES.glDeleteBuffers(1, &tempBuffer);
+            continue;
+        }
+
+        if (prevElementBuffer != 0) {
+            GLES.glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, prevElementBuffer);
+            srcData = GLES.glMapBufferRange(
+                    GL_ELEMENT_ARRAY_BUFFER,
+                    (GLintptr)currentIndices,
+                    currentCount * indexSize,
+                    GL_MAP_READ_BIT
+            );
+
+            if (!srcData) {
+                free(tempIndices);
+                GLES.glDeleteBuffers(1, &tempBuffer);
+                continue;
+            }
+        } else {
+            srcData = (void*)currentIndices;
+        }
+
+        switch (type) {
+            case GL_UNSIGNED_INT:
+                for (int j = 0; j < currentCount; ++j) {
+                    ((GLuint *)tempIndices)[j] = ((GLuint *)srcData)[j] + currentBaseVertex;
+                }
+                break;
+            case GL_UNSIGNED_SHORT:
+                for (int j = 0; j < currentCount; ++j) {
+                    ((GLushort *)tempIndices)[j] = ((GLushort *)srcData)[j] + currentBaseVertex;
+                }
+                break;
+            case GL_UNSIGNED_BYTE:
+                for (int j = 0; j < currentCount; ++j) {
+                    ((GLubyte *)tempIndices)[j] = ((GLubyte *)srcData)[j] + currentBaseVertex;
+                }
+                break;
+        }
+
+        if (prevElementBuffer != 0) {
+            GLES.glUnmapBuffer(GL_ELEMENT_ARRAY_BUFFER);
+        }
+
+        GLES.glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, tempBuffer);
+        GLES.glBufferData(GL_ELEMENT_ARRAY_BUFFER, currentCount * indexSize, tempIndices, GL_STREAM_DRAW);
+        free(tempIndices);
+        GLES.glDrawElements(mode, currentCount, type, 0);
+
+        GLES.glDeleteBuffers(1, &tempBuffer);
+    }
+
+    GLES.glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, prevElementBuffer);
+    
+    CHECK_GL_ERROR
+}
+
 void mg_glMultiDrawElementsBaseVertex_indirect(GLenum mode, GLsizei* counts, GLenum type, const void* const* indices, GLsizei primcount, const GLint* basevertex) {
     LOG()
 
@@ -125,6 +208,19 @@ void mg_glMultiDrawElements_indirect(GLenum mode, const GLsizei *count, GLenum t
     CHECK_GL_ERROR
 }
 
+void mg_glMultiDrawElements_drawelements(GLenum mode, const GLsizei *count, GLenum type, const void *const *indices, GLsizei primcount) {
+    LOG()
+
+    for (GLsizei i = 0; i < primcount; ++i) {
+        const GLsizei c = count[i];
+        if (c > 0) {
+            GLES.glDrawElements(mode, c, type, indices[i]);
+        }
+    }
+
+    CHECK_GL_ERROR
+}
+
 void mg_glMultiDrawElements_multiindirect(GLenum mode, const GLsizei *count, GLenum type, const void *const *indices, GLsizei primcount) {
     LOG()
 
@@ -152,8 +248,6 @@ void mg_glMultiDrawElements_basevertex(GLenum mode, const GLsizei *count, GLenum
 void glMultiDrawElementsBaseVertex(GLenum mode, GLsizei* counts, GLenum type, const void* const* indices, GLsizei primcount, const GLint* basevertex) {
     LOG()
 
-#ifdef DRAW_INDIRECT
-
     if (!g_indirect_cmds_inited) {
         GLES.glGenBuffers(1, &g_indirectbuffer);
         GLES.glBindBuffer(GL_DRAW_INDIRECT_BUFFER, g_indirectbuffer);
@@ -217,26 +311,12 @@ void glMultiDrawElementsBaseVertex(GLenum mode, GLsizei* counts, GLenum type, co
         GLES.glDrawElementsIndirect(mode, type, offset);
     }
 
-
-#else
-
-    for (GLsizei i = 0; i < primcount; ++i) {
-        const GLsizei count = counts[i];
-        if (count > 0) {
-            LOG_D("GLES.glDrawElementsBaseVertex, mode = %s, count = %d, type = %s, indices[i] = 0x%x, basevertex[i] = %d",
-                  glEnumToString(mode), count, glEnumToString(type), indices[i], basevertex[i])
-            GLES.glDrawElementsBaseVertex(mode, count, type, indices[i], basevertex[i]);
-        }
-    }
-#endif
-
     CHECK_GL_ERROR
 }
 
 void glMultiDrawElements(GLenum mode, const GLsizei* count, GLenum type, const void* const* indices, GLsizei primcount) {
     LOG()
 
-#ifdef DRAW_INDIRECT
     if (!g_indirect_cmds_inited) {
         GLES.glGenBuffers(1, &g_indirectbuffer);
         GLES.glBindBuffer(GL_DRAW_INDIRECT_BUFFER, g_indirectbuffer);
@@ -300,16 +380,6 @@ void glMultiDrawElements(GLenum mode, const GLsizei* count, GLenum type, const v
         GLES.glDrawElementsIndirect(mode, type, offset);
     }
 
-#else
-    
-    for (GLsizei i = 0; i < primcount; ++i) {
-        const GLsizei c = count[i];
-        if (c > 0) {
-            GLES.glDrawElements(mode, c, type, indices[i]);
-        }
-    }
-    
-#endif
 }
 
 // solve the crash error for ANGLE, but it will make Derivative Main with Optifine not work!

src/main/cpp/gl/drawing.h

@@ -37,12 +37,16 @@ GLAPI GLAPIENTRY void mg_glMultiDrawElementsBaseVertex_multiindirect(GLenum mode
 
 GLAPI GLAPIENTRY void mg_glMultiDrawElementsBaseVertex_basevertex(GLenum mode, GLsizei *counts, GLenum type, const void *const *indices, GLsizei primcount, const GLint *basevertex);
 
+GLAPI GLAPIENTRY void mg_glMultiDrawElementsBaseVertex_drawelements(GLenum mode, GLsizei *counts, GLenum type, const void *const *indices, GLsizei primcount, const GLint *basevertex);
+
 GLAPI GLAPIENTRY void mg_glMultiDrawElements_indirect(GLenum mode, const GLsizei *count, GLenum type, const void *const *indices, GLsizei primcount);
 
 GLAPI GLAPIENTRY void mg_glMultiDrawElements_multiindirect(GLenum mode, const GLsizei *count, GLenum type, const void *const *indices, GLsizei primcount);
 
 GLAPI GLAPIENTRY void mg_glMultiDrawElements_basevertex(GLenum mode, const GLsizei *count, GLenum type, const void *const *indices, GLsizei primcount);
 
+GLAPI GLAPIENTRY void mg_glMultiDrawElements_drawelements(GLenum mode, const GLsizei *count, GLenum type, const void *const *indices, GLsizei primcount);
+
 GLAPI GLAPIENTRY void glMultiDrawElements(GLenum mode, const GLsizei *count, GLenum type, const void *const *indices, GLsizei primcount);
 
 GLAPI GLAPIENTRY void glDrawElements(GLenum mode, GLsizei count, GLenum type, const void* indices);

src/main/cpp/glx/lookup.cpp

@@ -33,6 +33,9 @@ void* get_multidraw_func(const char* name) {
         case multidraw_mode_t::PreferMultidrawIndirect:
             namestr += "_multiindirect";
             break;
+        case multidraw_mode_t::DrawElements:
+            namestr += "_drawelements";
+            break;
         default:
             LOG_W("get_multidraw_func() cannot determine multidraw emulation mode!")
             return nullptr;
@@ -52,7 +55,7 @@ void *glXGetProcAddress(const char *name) {
 
     if (!proc) {
         fprintf(stderr, "Failed to get OpenGL function %s: %s\n", name, dlerror());
-        LOG_W("Failed to get OpenGL function: %s", (const char*)name);
+        LOG_W("Failed to get OpenGL function: %s", (const char*)name)
         return NULL;
     }
 
@@ -70,7 +73,7 @@ void *glXGetProcAddressARB(const char *name) {
 
     if (!proc) {
         fprintf(stderr, "Failed to get OpenGL function %s: %s\n", name, dlerror());
-        LOG_W("Failed to get OpenGL function: %s", (const char*)name);
+        LOG_W("Failed to get OpenGL function: %s", (const char*)name)
         return NULL;
     }