Merge pull request #480 from MaikelChan/depth_compare_fixes

Depth compare improvements based on GlideN64

port/fast3d/gfx_opengl.cpp

@@ -699,12 +699,42 @@ static void gfx_opengl_set_sampler_parameters(int tile, bool linear_filter, uint
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, gfx_cm_to_opengl(cmt));
 }
 
-static void gfx_opengl_set_depth_test_and_mask(bool depth_test, bool z_upd) {
-    if (depth_test || z_upd) {
+static void gfx_opengl_set_depth_mode(bool depth_test, bool depth_update, bool depth_compare, bool depth_source_prim, uint16_t zmode) {
+    if (depth_test) {
         glEnable(GL_DEPTH_TEST);
-        glDepthMask(z_upd ? GL_TRUE : GL_FALSE);
-        glDepthFunc(depth_test ? GL_LEQUAL : GL_ALWAYS);
-        current_depth_mask = z_upd;
+        glDepthMask(depth_update ? GL_TRUE : GL_FALSE);
+        current_depth_mask = depth_update;
+
+        if (depth_compare) {
+            switch (zmode) {
+                case ZMODE_INTER:
+                    glDepthFunc(GL_LEQUAL);
+                    glDisable(GL_POLYGON_OFFSET_FILL);
+                    glPolygonOffset(0, 0);
+                    break;
+
+                case ZMODE_OPA:
+                case ZMODE_XLU:
+                    if (depth_source_prim) {
+                        glDepthFunc(GL_LEQUAL);
+                    } else {
+                        glDepthFunc(GL_LESS);
+                    }
+                    glDisable(GL_POLYGON_OFFSET_FILL);
+                    glPolygonOffset(0, 0);
+                    break;
+
+                case ZMODE_DEC:
+                    glDepthFunc(GL_LEQUAL);
+                    glEnable(GL_POLYGON_OFFSET_FILL);
+                    glPolygonOffset(-2, -2);
+                    break;
+            }
+        } else {
+            glDepthFunc(GL_ALWAYS);
+            glDisable(GL_POLYGON_OFFSET_FILL);
+            glPolygonOffset(0, 0);
+        }
     } else {
         glDisable(GL_DEPTH_TEST);
     }
@@ -714,16 +744,6 @@ static void gfx_opengl_set_depth_range(float znear, float zfar) {
     glDepthRange(znear, zfar);
 }
 
-static void gfx_opengl_set_zmode_decal(bool zmode_decal) {
-    if (zmode_decal) {
-        glPolygonOffset(-2, -2);
-        glEnable(GL_POLYGON_OFFSET_FILL);
-    } else {
-        glPolygonOffset(0, 0);
-        glDisable(GL_POLYGON_OFFSET_FILL);
-    }
-}
-
 static void gfx_opengl_set_viewport(int x, int y, int width, int height) {
     glViewport(x, y, width, height);
 }
@@ -1156,9 +1176,8 @@ struct GfxRenderingAPI gfx_opengl_api = {
     gfx_opengl_select_texture,
     gfx_opengl_upload_texture,
     gfx_opengl_set_sampler_parameters,
-    gfx_opengl_set_depth_test_and_mask,
+    gfx_opengl_set_depth_mode,
     gfx_opengl_set_depth_range,
-    gfx_opengl_set_zmode_decal,
     gfx_opengl_set_viewport,
     gfx_opengl_set_scissor,
     gfx_opengl_set_use_alpha,

port/fast3d/gfx_pc.cpp

@@ -197,9 +197,8 @@ static struct RDP {
 } rdp;
 
 static struct RenderingState {
-    uint8_t depth_test_and_mask; // 1: depth test, 2: depth mask
+    uint8_t depth_mode;
     float depth_zfar;
-    bool decal_mode;
     bool alpha_blend;
     bool modulate;
     struct XYWidthHeight viewport, scissor;
@@ -1240,25 +1239,24 @@ static void gfx_sp_tri1(uint8_t vtx1_idx, uint8_t vtx2_idx, uint8_t vtx3_idx, bo
         }
     }
 
-    bool depth_test = (rsp.geometry_mode & G_ZBUFFER) == G_ZBUFFER;
-    bool depth_mask = (rdp.other_mode_l & Z_UPD) == Z_UPD;
-    uint8_t depth_test_and_mask = (depth_test ? 1 : 0) | (depth_mask ? 2 : 0);
-    if (depth_test_and_mask != rendering_state.depth_test_and_mask) {
-        gfx_flush();
-        gfx_rapi->set_depth_test_and_mask(depth_test, depth_mask);
-        rendering_state.depth_test_and_mask = depth_test_and_mask;
-    }
     if (rsp.depth_zfar != rendering_state.depth_zfar) {
         gfx_flush();
         gfx_rapi->set_depth_range(0.0f, rsp.depth_zfar);
         rendering_state.depth_zfar = rsp.depth_zfar;
     }
 
-    bool zmode_decal = (rdp.other_mode_l & ZMODE_DEC) == ZMODE_DEC;
-    if (zmode_decal != rendering_state.decal_mode) {
+    bool depth_test = ((rsp.geometry_mode & G_ZBUFFER) == G_ZBUFFER || (rdp.other_mode_l & G_ZS_PRIM) == G_ZS_PRIM) &&
+                      ((rdp.other_mode_h & G_CYC_1CYCLE) == G_CYC_1CYCLE || (rdp.other_mode_h & G_CYC_2CYCLE) == G_CYC_2CYCLE);
+    bool depth_update = (rdp.other_mode_l & Z_UPD) == Z_UPD;
+    bool depth_compare = (rdp.other_mode_l & Z_CMP) == Z_CMP;
+    bool depth_source_prim = (rdp.other_mode_l & G_ZS_PRIM) == G_ZS_PRIM /* && gDP.primDepth.z == 1.0f */;
+    uint16_t zmode = rdp.other_mode_l & ZMODE_DEC;
+    uint8_t depth_mode = (depth_test ? 1 : 0) | (depth_update ? 2 : 0) | (depth_compare ? 4 : 0) | (depth_source_prim ? 8 : 0) | (zmode >> 6);
+
+    if (depth_mode != rendering_state.depth_mode) {
         gfx_flush();
-        gfx_rapi->set_zmode_decal(zmode_decal);
-        rendering_state.decal_mode = zmode_decal;
+        gfx_rapi->set_depth_mode(depth_test, depth_update, depth_compare, depth_source_prim, zmode);
+        rendering_state.depth_mode = depth_mode;
     }
 
     if (rdp.viewport_or_scissor_changed) {

port/fast3d/gfx_rendering_api.h

@@ -27,9 +27,8 @@ struct GfxRenderingAPI {
     void (*select_texture)(int tile, uint32_t texture_id);
     void (*upload_texture)(const uint8_t* rgba32_buf, uint32_t width, uint32_t height);
     void (*set_sampler_parameters)(int sampler, bool linear_filter, uint32_t cms, uint32_t cmt);
-    void (*set_depth_test_and_mask)(bool depth_test, bool z_upd);
+    void (*set_depth_mode)(bool depth_test, bool depth_update, bool depth_compare, bool depth_source_prim, uint16_t zmode);
     void (*set_depth_range)(float znear, float zfar);
-    void (*set_zmode_decal)(bool zmode_decal);
     void (*set_viewport)(int x, int y, int width, int height);
     void (*set_scissor)(int x, int y, int width, int height);
     void (*set_use_alpha)(bool use_alpha, bool modulate);