cool-bun-demo/main.c

#include <stdio.h>

#include <clib/exec_protos.h>
#include <clib/graphics_protos.h>
#include <exec/exec.h>

#include <hardware/custom.h>
#include <hardware/dmabits.h>
#include <hardware/cia.h>

#include <graphics/gfx.h>

#include "system/blitter.h"
#include "system/copper.h"
#include "system/system.h"
#include "system/sprite.h"

#include "screen.h"
#include "types.h"
#include "bun.h"

extern struct Custom far custom;
extern struct CIA far ciaa;

// change to 0 to not render sprites
#define RENDER_SPRITES (1)

struct ScreenDefinition screenDefinition;
struct ActiveScreenBufferDetails activeScreenBufferDetails;

/**
 * The locations within the copperlist data where the bitplanes are referenced.
 * We change these areas of memory directly to implement double buffering.
 * Addresses are to the high, then low, word of the plane memory address in the copperlist.
 *
 * @see addDisplayToCopperlist
 */
void *copperlistBitplanePointers[8][2];

uint16_t custom_color = (uint16_t)offsetof(Custom, color);
uint16_t custom_sprite = (uint16_t)offsetof(Custom, sprpt);
uint16_t custom_sprite_control = (uint16_t)offsetof(Custom, spr);

extern uint8_t chip TopazBitplanes[];
extern uint16_t chip CopperColors[];
extern uint16_t chip SpriteCopperlist[];
extern uint16_t chip SpriteData[];
extern uint8_t chip MaskBitplane[];

#define TOPAZ_WIDTH_PIXELS (160)
#define TOPAZ_WIDTH_BYTES (TOPAZ_WIDTH_PIXELS / 8)
#define TOPAZ_WIDTH_WORDS (TOPAZ_WIDTH_PIXELS / 16)

#define BLTSIZE(w, h) (w + (h << 6))

void renderTopaz(void) {
  int plane;

  uint16_t bltcon0, bltcmod;
  uint8_t *bltbpt;

  bltcon0 = 0xca + (1 << 8) + (1 << 9) + (1 << 10) + (1 << 11);
  bltcmod = screenDefinition.byteWidth - TOPAZ_WIDTH_BYTES;
  bltbpt = TopazBitplanes;

  for (plane = 0; plane < 3; ++plane) {
    custom.bltcon0 = bltcon0;
    custom.bltcon1 = 0;
    custom.bltafwm = 0xffff;
    custom.bltalwm = 0xffff;
    custom.bltapt = MaskBitplane;
    custom.bltbpt = bltbpt;
    custom.bltcpt = activeScreenBufferDetails.planes[plane] + 8;
    custom.bltdpt = activeScreenBufferDetails.planes[plane] + 8;
    custom.bltamod = 0;
    custom.bltbmod = 0;
    custom.bltcmod = bltcmod;
    custom.bltdmod = bltcmod;
    custom.bltsize = BLTSIZE(TOPAZ_WIDTH_WORDS, 256);

    bltbpt += TOPAZ_WIDTH_BYTES * 256;

    WaitBlit();
  }
}

#define COPPERLIST_SIZE (10000)

uint16_t *copperlist;

void buildCopperlist(void) {
  uint32_t spriteDataPointer;
  uint16_t *currentCopperlist,
    *currentCopperColors,
    *currentSpriteCopperlist;
  int i, j, y;
  uint16_t spriteSetupRegisters[3];

  copperlist = prepareNewCopperlist(COPPERLIST_SIZE);

  currentCopperlist = addDisplayToCopperlist(
    copperlist,
    &screenDefinition,
    &activeScreenBufferDetails,
    &copperlistBitplanePointers
  );

  currentCopperColors = CopperColors;
  currentSpriteCopperlist = SpriteCopperlist;

  COPPERLIST_MOVE(currentCopperlist, custom_color, 0x3a6);
  COPPERLIST_MOVE(currentCopperlist, custom_color + 2, 0x000);
  COPPERLIST_MOVE(currentCopperlist, custom_color + 4, 0xfff);

  if (RENDER_SPRITES) {
    for (i = 0; i < 8; ++i) {
      spriteDataPointer = (uint32_t)&SpriteData;
      spriteDataPointer += ((256 + 2) * 4) * i;

      COPPERLIST_MOVE_POINTER(
        currentCopperlist,
        custom_sprite + i * 4,
        spriteDataPointer
      );
    }
  } else {
    printf("Skipping render\n");
    currentCopperlist = setUpEmptySpritesInCopperlist(currentCopperlist);
  }

  for (y = 0; y < 256; ++y) {
    if (RENDER_SPRITES) {
      for (i = 0; i < 8; ++i) {
        spriteSetupRegisters[0] = custom_color + 32 + (
          // sprite color group
          (i / 2) * 4 +
          // 0 is transparent
          1 +
          i % 2
        ) * 2;
        spriteSetupRegisters[1] = custom_sprite_control + i * 8;
        spriteSetupRegisters[2] = custom_sprite_control + i * 8 + 2;

        for (j = 0; j < 3; ++j) {
          COPPERLIST_MOVE(
            currentCopperlist,
            spriteSetupRegisters[j],
            *(currentSpriteCopperlist++)
          );
        }
      }
    } else {
      printf("Skipping render\n");
    }

    for (i = 3; i < 8; ++i) {
      COPPERLIST_MOVE(
        currentCopperlist,
        custom_color + (i * 2),
        *(currentCopperColors++)
      );
    }

    COPPERLIST_WAIT(
      currentCopperlist,
      (31 + (256 / 4)),
      (44 + y),
      0xFFFE
    );
  }

  endCopperlist(currentCopperlist);
}

void renderTopazPartials(
  uint16_t redrawRanges[BUN_COUNT][4]
) {
  int plane, i, topazX;

  uint16_t bltcon0;
  uint16_t bltamod, bltbmod, bltcmod, bltdmod;
  uint16_t width, height, bltsize;
  uint8_t *bltapt, *bltbpt, *bltcpt, *bltdpt;

  bltcon0 = 0xca + (1 << 8) + (1 << 9) + (1 << 10) + (1 << 11);
  bltcmod = screenDefinition.byteWidth;
  bltbpt = TopazBitplanes;


  for (i = 0; i < BUN_COUNT; ++i) {
    if (redrawRanges[i][2] - redrawRanges[i][0] < TOPAZ_WIDTH_PIXELS) {
      if (
        (redrawRanges[i][2] > 64 && redrawRanges[i][0] < (64 + TOPAZ_WIDTH_PIXELS)) ||
        (redrawRanges[i][0] < (64 + TOPAZ_WIDTH_PIXELS) && redrawRanges[i][2] > 64)
      ) {
        width = redrawRanges[i][2] - redrawRanges[i][0];
        height = redrawRanges[i][3] - redrawRanges[i][1];
        topazX = redrawRanges[i][0] - 64;

        if (topazX < 0) {
          topazX += 16;
          width -= 16;
        }
        // always round up to the next word
        width += 16;

        bltapt = redrawRanges[i][1] * TOPAZ_WIDTH_BYTES + (topazX >> 4) * 2;
        bltbpt = bltapt;
        bltcpt = redrawRanges[i][1] * screenDefinition.byteWidth + (redrawRanges[i][0] >> 4) * 2;
        bltdpt = bltcpt;

        bltamod = TOPAZ_WIDTH_BYTES - (width >> 4) * 2;
        bltbmod = bltamod;
        bltcmod = screenDefinition.byteWidth - (width >> 4) * 2;
        bltdmod = bltcmod;

        bltsize = BLTSIZE((width >> 4), height);

        printf(
          "Coords: %d, %d -> %d, %d\n",
          redrawRanges[i][0],
          redrawRanges[i][1],
          redrawRanges[i][2],
          redrawRanges[i][3]
        );

        printf("topazX: %d\n", topazX);
        printf("width: %d\n", width);

        printf("BLTAPT: %d\n", bltapt);
        printf("BLTBPT: %d\n", bltbpt);
        printf("BLTCPT: %d\n", bltcpt);
        printf("BLTDPT: %d\n", bltdpt);

        printf("BLTAMOD: %d\n", bltamod);
        printf("BLTBMOD: %d\n", bltbmod);
        printf("BLTCMOD: %d\n", bltcmod);
        printf("BLTDMOD: %d\n", bltdmod);

        printf("BLTSIZE: %d, %d\n", (width >> 4), height);

        /*
        for (plane = 0; plane < 3; ++plane) {
          custom.bltcon0 = bltcon0;
          custom.bltcon1 = 0;
          custom.bltafwm = 0xffff;
          custom.bltalwm = 0xffff;
          custom.bltapt = MaskBitplane;
          custom.bltbpt = bltbpt;
          custom.bltcpt = activeScreenBufferDetails.planes[plane] + 8;
          custom.bltdpt = activeScreenBufferDetails.planes[plane] + 8;
          custom.bltamod = 0;
          custom.bltbmod = 0;
          custom.bltcmod = bltcmod;
          custom.bltdmod = bltcmod;
          custom.bltsize = BLTSIZE(TOPAZ_WIDTH_WORDS, 256);

          bltbpt += TOPAZ_WIDTH_BYTES * 256;

          WaitBlit();
        }
        */
      }
    }
  }
}

int main(void) {
  int i;

  struct BunRenderer bunRenderer;
  uint16_t redrawRanges[BUN_COUNT][4];

  printf("\nCool bun blitter, copper, and sprite demo by John Bintz\n");
  printf("\n");
  printf("This is my first real go at writing graphics code for the Amiga.\n");
  printf("It's a combination of C (SAS/C) and Assembler (DevPac), with a Ruby\n");
  printf("script to do some image processing. The screen only uses three\n");
  printf("bitplanes -- one color is the background, two colors are the flying\n");
  printf("cool bun logo white and black, and the remaining 5 colors are used\n");
  printf("by the Topaz smiling art. The Ruby script will process the PNG file\n");
  printf("and figure out the best 5 colors (plus b&w) for that line of the\n");
  printf("image, setting the colors via copperlist for that line.\n");
  printf("It also builds the clipping mask for the blitter.\n\n");

  printf("And, I'm also using sprites to add more colors to the Topaz art.\n");
  printf("The Ruby script will figure out what small areas of each line weren't\n");
  printf("covered by the bitplane colors and use the 8 available sprites,\n");
  printf("changing the colors on each line via copper, to fill in the gaps.\n");
  printf("Cool buns are animated via blitter rather than sprites, but I\n");
  printf("managed to get it to run at a decent speed regardless.\n");

  printf("\nEnjoy, and thanks for watching!\n");
  printf("John (theindustriousrabbit.com)\n\n");

  allocateDoubleBufferedScreenMemory(
    &screenDefinition,
    &activeScreenBufferDetails,
    SCREEN_WIDTH,
    SCREEN_HEIGHT,
    3
  );

  setupBunRenderer(
    &bunRenderer,
    &screenDefinition,
    &activeScreenBufferDetails
  );

  buildCopperlist();


  /*
  copperlist debugging
  for (i = 0; i < 20; ++i) {
    printf(
      "%x %x %x %x\n",
      *(copperlist + (i * 4)),
      *(copperlist + (i * 4) + 1),
      *(copperlist + (i * 4) + 2),
      *(copperlist + (i * 4) + 3)
    );
  }
  */

  calculateNeededRedrawRanges(0, redrawRanges);
  renderTopazPartials(redrawRanges);

  /*
  takeOverSystem();

  setCopperlist(copperlist);
  setUpDisplay((uint32_t)screenDefinition.bitplanes);

  renderTopaz();
  swapCurrentScreenBuffer(&screenDefinition, &activeScreenBufferDetails);
  renderTopaz();
  swapCurrentScreenBuffer(&screenDefinition, &activeScreenBufferDetails);

  i = 0;


  while (0) {
    swapCurrentScreenBuffer(&screenDefinition, &activeScreenBufferDetails);


    clearCurrentBuns(&bunRenderer);
    renderBunFrame(i, &bunRenderer);


    updateDisplayInCopperList(
      &screenDefinition,
      &activeScreenBufferDetails,
      copperlistBitplanePointers
    );

    WaitBOF(250);

    if ((ciaa.ciapra >> 6) != 3) break;

    i++;
    //i %= FRAMES_FOR_SCREEN;
  }

  giveBackSystem();
  */

  teardownScreen(&screenDefinition);

  freeCopperlist(copperlist);

  teardownBunRenderer();

  return 0;
}