; Draws the hardcoded spark sprite with the given ID at the given position. ; pointing to the top-left point. Assumptions: ; • ES is already be set to the beginning of a VRAM segment ; • The GRCG is active, and set to the intended color ; void near fastcall spark_render(screen_x_t left, vram_y_t top, int sprite_id); public @spark_render @spark_render proc near push si push di mov si, ax ; SI = [x] mov bx, dx ; BX = [vram_y] sar ax, 3 ; x / 8 shl dx, 6 ; [vram_y] * 64 add ax, dx shr dx, 2 ; (([vram_y] * 64) / 4) = [vram_y] * 16 add ax, dx mov di, ax ; ([vram_y] * 64) + ([vram_y] * 16) = [vram_y * ROW_SIZE] and si, 7 ; [x] & 7 mov ax, si shl si, 7 ; *= SPARK_SIZE * SPARK_SPRITES (offset of X-shifted sprite) add si, offset _sSPARKS and cx, 7 ; & (SPARK_SPRITES - 1) shl cx, 4 ; * SPARK_SIZE add si, cx blit_dots16_empty2opt_emptyopt_roll , SPARK_H @@ret: pop di pop si retn @spark_render endp even