Further performance improvements

4 files changed, 52 insertions, 44 deletions

diff --git a/Makefile b/Makefile
index 60a141c..89ea9b0 100644
--- a/Makefile
+++ b/Makefile
@@ -27,7 +27,7 @@ INC_FLAGS   := $(addprefix -I,$(INC_DIRS))
 INC_FLAGS   += -I$(LIBGBA_SRC)
 
 # Output library names and executables.
-TARGET         := STEPPER-v1.8-dev-20
+TARGET         := STEPPER-v1.8-dev-21
 ELF            := $(BUILD_DIR)/$(TARGET).elf
 BIN            := $(BUILD_DIR)/$(TARGET).gba
 
diff --git a/src/globals.c b/src/globals.c
index c040585..9d0a5bb 100644
--- a/src/globals.c
+++ b/src/globals.c
@@ -236,3 +236,4 @@ static int wave_env_ticks = 0;
 static int wave_env_attack = 8;
 static int wave_env_decay = 8;
 static int wave_env_prog = 0;
+static Wave current_wave[8] = {0};
diff --git a/src/main.c b/src/main.c
index 2731b6a..a4d3421 100644
--- a/src/main.c
+++ b/src/main.c
@@ -71,6 +71,8 @@ WITH REGARD TO THIS SOFTWARE.
 #define PROF_ENABLE 0
 #include "profiling.c"
 
+static int frames = 0;
+
 void
 render_sequencer(void) {
     if (redraw_trigs) {
@@ -110,11 +112,15 @@ render_sequencer(void) {
 
     if (input_handler == handle_pattern_selection ||
             input_handler == handle_pattern_chain) {
-        draw_pattern_chain();
+        if (frames & 0x1) {
+            draw_pattern_chain();
+        }
     }
 
-    draw_notif_bar();
-    PROF(draw_piano_notes(), draw_piano_cycles);
+    if (frames++ & 0x1) {
+        draw_notif_bar();
+        PROF(draw_piano_notes(), draw_piano_cycles);
+    }
     PROF(draw_cursors(), draw_cursor_cycles);
 }
 
diff --git a/src/sequencer.c b/src/sequencer.c
index 45fc0e4..c01f905 100644
--- a/src/sequencer.c
+++ b/src/sequencer.c
@@ -376,12 +376,37 @@ wave_ad_tick(void) {
 env_start:
     switch (wave_env) {
         case WAV_ENV_START: {
+            // Calculate all 8 transitions for the current target wave.
+            for (size_t k = 0; k < 8; k++) {
+                for (size_t j = 0; j < 4; j++) {
+                    u32 next = 0;
+                    u32 prev = (*wave_target)[j];
+                    for (size_t i = 0; i < 8; i++) {
+                        u8 val = (prev >> 4 * i) & 0xF;
+                        u8 tmp = mult_table[val][k];
+                        next |= (tmp << 4 * i);
+                    }
+                    current_wave[k][j] = next;
+                }
+                // DEBUG:
+                // if (k < 4) {
+                //     int x = 0;
+                //     int y = 18 * k;
+                //     draw_filled_rect(x, y, 100 + x, 16 + y, COL_BG);
+                //     draw_wave_pattern(&current_wave[k], 0 + x, 0 + y, 1);
+                // } else {
+                //     int x = 100;
+                //     int y = 18 * (k - 4);
+                //     draw_filled_rect(x, y, 100 + x, 16 + y, COL_BG);
+                //     draw_wave_pattern(&current_wave[k], 0 + x, 0 + y, 1);
+                // }
+            }
             wave_env_ticks = 0;
             wave_env_prog = 0;
             SOUND_WAVE_MODE = SOUND_WAVE_BANK_SELECT(0);
-            memcpy32(SOUND_WAVE_RAM, wave_zero, 16);
+            memcpy32(SOUND_WAVE_RAM, current_wave[0], 16);
             SOUND_WAVE_MODE = SOUND_WAVE_BANK_SELECT(1);
-            memcpy32(SOUND_WAVE_RAM, wave_zero, 16);
+            memcpy32(SOUND_WAVE_RAM, current_wave[0], 16);
             SOUND_WAVE_MODE = SOUND_WAVE_BANK_MODE(0)
                 | SOUND_WAVE_BANK_SELECT(0);
             SOUND_WAVE_MODE |= SOUND_WAVE_ENABLE;
@@ -411,17 +436,14 @@ env_start:
             }
             wave_env_ticks = 0;
 
-            // Attack.
-            for (size_t j = 0; j < 4; j++) {
-                u32 next = 0;
-                u32 prev = (*wave_target)[j];
-                for (size_t i = 0; i < 8; i++) {
-                    u8 val = (prev >> 4 * i) & 0xF;
-                    u8 tmp = mult_table[val][wave_env_prog];
-                    next |= (tmp << 4 * i);
-                }
-                wave_active[j] = next;
-            }
+            // DEBUG:
+            // int x = 50;
+            // int y = 50;
+            // draw_filled_rect(0 + x, 0 + y, 100 + x, 32 + y, COL_BG);
+            // draw_wave_pattern(&current_wave[wave_env_prog], 0 + x, 0 + y, 1);
+
+            memcpy32(SOUND_WAVE_RAM, current_wave[wave_env_prog], 16);
+            SOUND_WAVE_MODE ^= SOUND_WAVE_BANK_SELECT(1);
             if (++wave_env_prog >= 8) {
                 if (wave_env_decay == 0) {
                     wave_env = WAV_ENV_OFF;
@@ -430,15 +452,6 @@ env_start:
                 }
                 wave_env_prog = 0;
             }
-
-            // DEBUG:
-            // int x = 50;
-            // int y = 50;
-            // draw_filled_rect(0 + x, 0 + y, 100 + x, 32 + y, COL_BG);
-            // draw_wave_pattern(&wave_active, 0 + x, 0 + y, 1);
-
-            memcpy32(SOUND_WAVE_RAM, wave_active, 16);
-            SOUND_WAVE_MODE ^= SOUND_WAVE_BANK_SELECT(1);
         } break;
         case WAV_ENV_DECAY: {
             if (wave_env_ticks++ < wave_env_decay) {
@@ -446,30 +459,18 @@ env_start:
             }
             wave_env_ticks = 0;
 
-            // Decay.
-            for (size_t j = 0; j < 4; j++) {
-                u32 next = 0;
-                u32 prev = (*wave_target)[j];
-                for (size_t i = 0; i < 8; i++) {
-                    u8 val = (prev >> 4 * i) & 0xF;
-                    u8 tmp = mult_table[val][7 - wave_env_prog];
-                    next |= (tmp << 4 * i);
-                }
-                wave_active[j] = next;
-            }
-            if (++wave_env_prog >= 8) {
-                wave_env = WAV_ENV_END;
-                wave_env_prog = 0;
-            }
-
             // DEBUG:
             // int x = 50;
             // int y = 50;
             // draw_filled_rect(0 + x, 0 + y, 100 + x, 32 + y, COL_BG);
-            // draw_wave_pattern(&wave_active, 0 + x, 0 + y, 1);
+            // draw_wave_pattern(&current_wave[7-wave_env_prog], 0 + x, 0 + y, 1);
 
-            memcpy32(SOUND_WAVE_RAM, wave_active, 16);
+            memcpy32(SOUND_WAVE_RAM, current_wave[7 - wave_env_prog], 16);
             SOUND_WAVE_MODE ^= SOUND_WAVE_BANK_SELECT(1);
+            if (++wave_env_prog >= 8) {
+                wave_env = WAV_ENV_END;
+                wave_env_prog = 0;
+            }
         } break;
         case WAV_ENV_OFF: {
             if (wave_env_ticks++ == 24) {