From 976a29bc4205681db1ef50144781d78c4a9b39d0 Mon Sep 17 00:00:00 2001 From: Michael Georgoulopoulos Date: Sun, 18 Sep 2016 18:15:01 +0300 Subject: [PATCH] Made RLE streak width/position scaling use fixed point + updated RLE scanline interpolator to handle blank streaks --- src/grise.c | 45 +++++++++++++++++++++++++++++++++++---------- 1 file changed, 35 insertions(+), 10 deletions(-) diff --git a/src/grise.c b/src/grise.c index 896b7c0..e6debce 100644 --- a/src/grise.c +++ b/src/grise.c @@ -33,7 +33,7 @@ static RLEBitmap rleEncode(unsigned char *pixels, unsigned int w, unsigned int h #define PIXEL_PADDING 32 /* Make sure this is less than PIXEL_PADDING*/ -#define MAX_DISPLACEMENT 16 +#define MAX_DISPLACEMENT 16 #define MIN_SCROLL PIXEL_PADDING #define MAX_SCROLL (backgroundW - fb_width - MIN_SCROLL) @@ -202,7 +202,8 @@ static void draw(void) } /* Then after displacement, blit the objects */ - for (i = 0; i < 5; i++) rleBlit(backBuffer + PIXEL_PADDING, fb_width, fb_height, BB_SIZE, grobj, 134 + (i-3) * 60, 100); + //for (i = 0; i < 5; i++) rleBlit(backBuffer + PIXEL_PADDING, fb_width, fb_height, BB_SIZE, grobj, 134 + (i-3) * 60, 100); + for (i = 0; i < 5; i++) rleBlitScale(backBuffer + PIXEL_PADDING, fb_width, fb_height, BB_SIZE, grobj, 134 + (i - 3) * 120, 0, 1.8f, 1.8f); /* Blit effect to framebuffer */ src = backBuffer + PIXEL_PADDING; @@ -313,9 +314,11 @@ static void updateScrollTables(float dt) { #define RLE_STREAKS_PER_SCANLINE 4 /* Every streak is encoded by 2 bytes: offset and count of black pixels in the streak */ #define RLE_BYTES_PER_SCANLINE RLE_STREAKS_PER_SCANLINE * 2 -#define RLE_FILL_COLOR 0 +#define RLE_FILL_COLOR 0xFF00 #define RLE_FILL_COLOR_32 ((RLE_FILL_COLOR << 16) | RLE_FILL_COLOR) +#define RLE_FIXED_BITS 16 + static RLEBitmap rleCreate(unsigned int w, unsigned int h) { RLEBitmap ret; ret.w = w; @@ -433,7 +436,17 @@ static void interpolateScan(unsigned char *output, unsigned char *a, unsigned ch ti = (*((unsigned int*)&t)) & 0x7FFFFF; for (i = 0; i < RLE_BYTES_PER_SCANLINE; i++) { - *output++ = ((*b++ * ti) + (*a++ * (div - ti))) >> 23; + if (*a == 0) { + *output++ = *b++; + a++; + } else { + if (*b == 0) { + *output++ = *a++; + b++; + } else { + *output++ = ((*b++ * ti) + (*a++ * (div - ti))) >> 23; + } + } } } @@ -452,11 +465,16 @@ static void rleBlitScale(unsigned short *dst, int dstW, int dstH, int dstStride, int blitW = (int) (bitmap.w * scaleX + 0.5f); int blitH = (int)(bitmap.h * scaleY + 0.5f); + + /* From this point on, scaleY will be inverted */ + scaleY = 1.0f / scaleY; + + int scaleXFixed = (int)(scaleX * (float)(1 << RLE_FIXED_BITS) + 0.5f); dst += blitX + blitY * dstStride; for (scanline = blitY; scanline < blitY + blitH; scanline++) { - float normalScan = scanlineCounter / scaleY; + float normalScan = scanlineCounter * scaleY; /* ScaleY is inverted */ unsigned char *scan0 = bitmap.scans + RLE_BYTES_PER_SCANLINE * (int)normalScan; unsigned char *scan1 = scan0 + RLE_BYTES_PER_SCANLINE; normalScan -= (int)normalScan; @@ -466,8 +484,8 @@ static void rleBlitScale(unsigned short *dst, int dstW, int dstH, int dstStride, if (scanline < 0 || scanline >= dstH) continue; for (streak = 0; streak < RLE_STREAKS_PER_SCANLINE; streak++) { - streakPos = (int) ((*input++) * scaleX + 0.5f); - streakLength = (int)((*input++) * scaleX + 0.5f); + streakPos = (*input++ * scaleXFixed) >> RLE_FIXED_BITS; + streakLength = (*input++ * scaleXFixed) >> RLE_FIXED_BITS; if ((streakPos + blitX) <= 0) continue; @@ -490,6 +508,8 @@ static void rleBlitScale(unsigned short *dst, int dstW, int dstH, int dstStride, } } + + static void rleBlitScaleInv(unsigned short *dst, int dstW, int dstH, int dstStride, RLEBitmap bitmap, int blitX, int blitY, float scaleX, float scaleY) { @@ -506,10 +526,15 @@ static void rleBlitScaleInv(unsigned short *dst, int dstW, int dstH, int dstStri int blitW = (int)(bitmap.w * scaleX + 0.5f); int blitH = (int)(bitmap.h * scaleY + 0.5f); + /* From this point on, scaleY will be inverted */ + scaleY = 1.0f / scaleY; + + int scaleXFixed = (int)(scaleX * (float)(1 << RLE_FIXED_BITS) + 0.5f); + dst += blitX + blitY * dstStride; for (scanline = blitY; scanline > blitY - blitH; scanline--) { - float normalScan = scanlineCounter / scaleY; + float normalScan = scanlineCounter * scaleY; /* ScaleY is inverted */ unsigned char *scan0 = bitmap.scans + RLE_BYTES_PER_SCANLINE * (int)normalScan; unsigned char *scan1 = scan0 + RLE_BYTES_PER_SCANLINE; normalScan -= (int)normalScan; @@ -519,8 +544,8 @@ static void rleBlitScaleInv(unsigned short *dst, int dstW, int dstH, int dstStri if (scanline < 0 || scanline >= dstH) continue; for (streak = 0; streak < RLE_STREAKS_PER_SCANLINE; streak++) { - streakPos = (int)((*input++) * scaleX + 0.5f); - streakLength = (int)((*input++) * scaleX + 0.5f); + streakPos = (*input++ * scaleXFixed) >> RLE_FIXED_BITS; + streakLength = (*input++ * scaleXFixed) >> RLE_FIXED_BITS; if ((streakPos + blitX) <= 0) continue; -- 1.7.10.4